MgO–C refractories are extensively employed in critical metallurgical equipment such as converters, electric arc furnaces and ladles, valued for their exceptional thermal shock resistance and slag corrosion resistanc...MgO–C refractories are extensively employed in critical metallurgical equipment such as converters, electric arc furnaces and ladles, valued for their exceptional thermal shock resistance and slag corrosion resistance. However, the use of high-proportion scrap steel in low-carbon steelmaking processes accelerates the corrosive degradation of MgO–C refractories due to changes in slag basicity and viscosity. Enhancing the slag corrosion resistance of MgO–C refractories has thus become an urgent priority. The methods for evaluating the slag corrosion resistance of MgO–C refractories are systematically reviewed, the slag corrosion mechanisms are elucidated, and various strategies and recent advances for enhancing their slag corrosion resistance are summarized. The aim is to provide valuable insights and references for ongoing research in this field while outlining potential directions for future studies.展开更多
In this study,FeCr_(x)MnAlCu(x=0,0.5,1.0,1.5,2.0)high-entropy alloys were fabricated using vacuum arc melting,and the corrosion behavior of these alloys in 3.5wt%NaCl solution at room temperature was investigated by e...In this study,FeCr_(x)MnAlCu(x=0,0.5,1.0,1.5,2.0)high-entropy alloys were fabricated using vacuum arc melting,and the corrosion behavior of these alloys in 3.5wt%NaCl solution at room temperature was investigated by electrochemical dynamic potential polarization curves and immersion experiments.The microstructure results show that the high-entropy alloy with x=0 has a body-centered cubic phase structure,whereas the high-entropy alloys with x=0.5–2.0 have a mixed face-centered cubic+body-centered cubic dual-phase structure.The corrosion results show that the corrosion resistance of the high-entropy alloy is increased with the increase in Cr content.Among them,the high-entropy alloy with x=2.0 exhibits the optimal corrosion resistance:the highest self-corrosion potential(E_(corr)=−0.354 V vs.Ag/AgCl),the smallest self-corrosion current density(I_(corr)=1.991×10^(−6)A·cm^(−2)),and the smallest corrosion rate(0.0292 mm/a).The composite passivation film of oxides and hydroxides is formed on the surface of the corroded high-entropy alloys,and the Cr_(2)O_(3)content is increased with the increase in Cr content,which effectively improves the stability and protective properties of the passivation film.展开更多
The J55 tubing thread fastener in an electric pump well experienced corrosion failure.The causes of the failure were investigated through physical and chemical property tests,corrosion product analysis,and microbial a...The J55 tubing thread fastener in an electric pump well experienced corrosion failure.The causes of the failure were investigated through physical and chemical property tests,corrosion product analysis,and microbial analysis.The results show that the metallographic structure and composition of the J55 tubing were normal.CO 2 corrosion was not the main cause of the thread fastener failure.The actual cause of the corrosion failure was microbiological corrosion,such as sulfate-reducing bacteria,thiosulfate-reducing bacteria,and iron-oxidizing bacteria.展开更多
Seawater electrolysis has been explored as a viable and sustainable method for green hydrogen production in regions characterized by freshwater scarcity but abundant renewable energy resources.However,the high concent...Seawater electrolysis has been explored as a viable and sustainable method for green hydrogen production in regions characterized by freshwater scarcity but abundant renewable energy resources.However,the high concentration of chlorine ions(Cl^(-))in seawater leads to severe corrosion of metallic electrodes,which significantly challenges the stability of electrode catalysts in seawater electrolysis.Owing to the Cl^(-)corrosion and the competitive oxygen/chlorine evolution reactions,the design of durable and active anode catalysts is key to achieving practical seawater electrolysis.To address this challenge,this review systematically analyzes the chlorine-induced corrosion mechanisms of anode catalysts,evaluates various anticorrosion strategies,and explores future prospects for enhancing anode durability.Three mainstream anticorrosion strategies are summarized and assessed for their effectiveness in mitigating the chlorineinduced damage to anode catalysts:the physical surface coatings,electrostatic repulsion,and Cl^(-)adsorption regulation.In addition,some emerging strategies are further introduced to highlight the future trends of state-of-the-art techniques for seawater electrolysis.This review aims to provide novel insights and practical guidance for developing more stable and efficient anode catalysts for hydrogen production via seawater electrolvsis.展开更多
Coating-free press-hardened steel(CF-PHS)had effectively tackled the challenge of high-temperature oxidation during processing through Cr-Si alloying strategy.However,it is equally essential to investigate its corrosi...Coating-free press-hardened steel(CF-PHS)had effectively tackled the challenge of high-temperature oxidation during processing through Cr-Si alloying strategy.However,it is equally essential to investigate its corrosion resistance and the role of the oxide scale in corrosion environments.The corrosion resistance of CF-PHS with and without oxide scale was comprehensively evaluated by analyzing electrochemical processes and corrosion products,as well as characterizing the corroded oxide scale features,while comparing it with commercial 22MnB5 steel.The results indicate that CF-PHS exhibits superior corrosion resistance compared to 22MnB5 steel and the presence of oxide scale may have a negative influence on short-time corrosion resistance.The ultra-thin oxide scale is unable to effectively and timely mitigate pit propagation during the rapid electrochemical tests.Conversely,during the prolonged corrosion process,the oxide scale can still function as the physical barrier to provide protective effects,making the corrosion process develop more slowly and evenly.展开更多
This study utilizes wet/dry cyclic corrosion testing combined with corrosion big data technology to investigate the mechanism by which chloride ions(Cl^(-))influence the corrosion behavior of 650 MPa high-strength low...This study utilizes wet/dry cyclic corrosion testing combined with corrosion big data technology to investigate the mechanism by which chloride ions(Cl^(-))influence the corrosion behavior of 650 MPa high-strength low-alloy(HSLA)steel in industrially polluted environments.The corrosion process of 650 MPa HSLA steel occurred in two distinct stages:an initial corrosion stage and a stable corrosion stage.During the initial phase,the weight loss rate increased rapidly owing to the instability of the rust layer.Notably,this study demonstrated that 650 MPa HSLA steel exhibited superior corrosion resistance in Cl-containing environments.The formation of a corrosion-product film eventually reduced the weight-loss rate.However,the intrusion of Cl^(-)at increasing concentrations gradually destabilized theα/γ^(*)phases of the rust layer,leading to a looser structure and lower polarization resistance(R_(p)).The application of corrosion big data technology in this study facilitated the validation and analysis of the experimental results,offering new insights into the corrosion mechanisms of HSLA steel in chloride-rich environments.展开更多
High-purity graphite is extensively utilized in the semiconductor industry.Enhancing its corrosion resistance is crucial for reducing the manufacturing costs of the third-generation semiconductors.In this study,a cont...High-purity graphite is extensively utilized in the semiconductor industry.Enhancing its corrosion resistance is crucial for reducing the manufacturing costs of the third-generation semiconductors.In this study,a continuous and dense TaC coating was fabricated on the surface of graphite using CVD method.The corrosion resistance and mechanism of the coating were investigated in a high-temperature steam environment.This environment involved temperatures exceeding 2200 K and the erosion of the coating by Si-containing mixed steam flows.The results indicated that the corrosion in the affected areas was primarily due to chemical reactions,characterized by the formation of pores and micro-cracks,whereas failure areas were dominated by mechanical delamination,which led to macroscopic defects.Moreover,the mixed high-temperature steam corrosion of the TaC coating showed preferential selectivity,resulting in a stepped corrosion morphology at the crystalline level.The surface roughness of the samples significantly increased after corrosion,from 0.36 to 5.28μm,although the surface composition remained largely unchanged.The TaC coating provides a certain level of protection to the graphite substrate,enhancing the service life of graphite components and demonstrating promising application potential.展开更多
The TiB+TiC dual-reinforced B_(4)C/TC4 composite was in-situ fabricated via incorporating 0.5wt%B_(4)C reinforcement during the laser melting deposition process.Different heat treatments of annealing and solid solutio...The TiB+TiC dual-reinforced B_(4)C/TC4 composite was in-situ fabricated via incorporating 0.5wt%B_(4)C reinforcement during the laser melting deposition process.Different heat treatments of annealing and solid solution were used to regulate the microstructure,mechanical properties,and corrosion properties of B_(4)C/TC4 composite.Results show that with the increase in temperature from 500℃to 800°C,partial lamellarα-Ti in the as-deposited sample is gradually transformed into equiaxedα-Ti,accompanied by the disappearance of basketweave microstructure.At 1100°C,a small portion of TiC phase suffers fusion.This composite exhibits the optimal combination of strength and plasticity after annealing at 500℃for 4 h followed by furnace cooling,which is attributed to the stress release effect and the refined basketweave microstructure.However,this composite shows a decline in corrosion resistance after various heat treatments due to grain coarsening and micro-galvanic corrosion.展开更多
Photoelectrochemical seawater splitting is promising for renewable hydrogen,yet severe chloride corrosion remains a roadblock.Although amorphous catalysts improve hematite(α-Fe_(2)O_(3))photoanode activity,their defe...Photoelectrochemical seawater splitting is promising for renewable hydrogen,yet severe chloride corrosion remains a roadblock.Although amorphous catalysts improve hematite(α-Fe_(2)O_(3))photoanode activity,their defect-enabled functionality inherently accelerates structural degradation,exacerbating chloride-induced corrosion.Here,a synergistic dual-functional nano-armor is designed by anchoring phosphate(PO_(4)^(3-))to active sites on amorphous NiMoO_(4)(a-NiMoO_(4)@PO_(4)^(3-)),achieving dual activitystability enhancement.Detailed physicochemical characterization and density functional theory(DFT)calculations show that the successful and stable anchoring of phosphate is highly dependent on the amorphous structural properties of a-NiMoO_(4).Its rich disordered coordination environment provides sufficient highly reactive sites,allowing PO_(4)^(3-)to be firmly bound through strong coordination bonds,which is the key for the dual role of PO_(4)^(3-)coordination.As a dynamic Cl-shield,PO_(4)^(3-)coordinates unsaturated Ni sites,forming an anionic layer that resists Cl-via steric-electrostatic blocking.As an electronic modulator,PO_(4)^(3-)triggers metal-to-ligand charge transfer at Ni sites,depleting electron density to optimize the intermediate adsorption of oxygen evolution reaction(OER)and reduce kinetic barriers.Simultaneously,this charge redistribution induces a built-in electric field that accelerates holeselective transport.Benefiting from these dual effects,the Fe_(2)O_(3)/a-NiMoO_(4)@PO_(4)^(3-)achieves 4 mA cm^(-2)at 1.23 V_(RHE) with exceptional stability in seawater.This work leverages the unique coordination flexibility of amorphous structures to construct a phosphate-coordinated bifunctional nano-armor on hematite photoanodes,which simultaneously enables efficient chloride exclusion and electronic structure optimization.The synergistic mechanism,rooted in strong phosphate anchoring on amorphous carriers,establishes a new design paradigm for photoelectrochemical systems that integrate high activity with extreme environmental stability,providing an efficient pathway toward corrosion-resistant seawater splitting.展开更多
The synergistic effects of corrosion and impact loading on the microstructure evolution and dynamic mechanical properties of ultrahigh-strength AerMet 100 steel are investigated.Through integrated experiments and mode...The synergistic effects of corrosion and impact loading on the microstructure evolution and dynamic mechanical properties of ultrahigh-strength AerMet 100 steel are investigated.Through integrated experiments and modeling,the result reveals that the corrosion leads to grain refinement and a reduction in the proportion of low-angle grain boundaries.Notably,corrosion promotes austenite enrichment(increasing from 1.8%to 13.9%)through selective dissolution of the martensitic matrix,while repetitive impacts reverse this trend(reducing to 0.1%)through stress-induced martensitic transformation.Fracture analysis demonstrates corrosion-induced ductile-to-brittle transition,with quasi-cleavage features dominating after prolonged corrosion.A physics-based dynamic yield strength model with<3%prediction error relative to impact tests is developed.These findings establish microstructure-property relationships of AerMet 100 steel under multi-field coupling,providing critical guidance for designing corrosion-resistant ultrahigh-strength steels in marine-impact environments.展开更多
Through investigating the influence of electrochemically charged hydrogen on microstructural damage and corrosion performance of an as-cast Ti-6Al-4V(in wt.%)alloy,it demonstrated that after being performed hydrogen-c...Through investigating the influence of electrochemically charged hydrogen on microstructural damage and corrosion performance of an as-cast Ti-6Al-4V(in wt.%)alloy,it demonstrated that after being performed hydrogen-charging for 4 h at an applied current density value of 50 mA/cm^(2),micro cracks were preferentially presented in α-Ti phase and at interfaces between α-Ti and β-Ti phases.Moreover,the quantity of cracks increased with extending the hydrogen-charging time.Failure analysis demonstrated that micro cracks were caused by the formation of needle-like δ-TiH2 hydride.For 4 h-charged sample,all of the exposed α-Ti phase can be changed into hydrides,resulting in the formation of a layer of hydride with the thickness value of 5μm.After hydrogen-charging for 8 and 16 h,the thicknesses values of formed hydride layers were 8 and 18μm,respectively.Due to anodic dissolution of hydrides,the corrosion resistance of charged samples was degraded.The determined current density values of the uncharged,4 h-charged,8 h-charged and 16 h-charged samples were 34.7,42.3,50.7 and 63.4 nA/cm^(2),respectively.展开更多
Hydrochloric acid(HCl)extensively exists in deep underground projects,arising from the transportation of industrial raw materials or fracturing fluids of petroleum engineering.It results in corrosion,which can signifi...Hydrochloric acid(HCl)extensively exists in deep underground projects,arising from the transportation of industrial raw materials or fracturing fluids of petroleum engineering.It results in corrosion,which can significantly impact the stability of surrounding rock structures.Therefore,in-depth analysis of the degradation of rock corroded by the HCl solution is an essential task for underground engineering.In this study,the granite specimens are initially treated with the HCl solution with various concentrations.Then,the tests and analyses,such as electrical conductivity(EC)measurements,mineral composition assays,and Brazilian splitting tests,are employed to investigate the corrosion mechanism of the HCl solution.Our results and findings are generally as follows:(1)As the immersion time increases,the EC exhibits a relatively high level at pH value of 1,a decreasing trend at pH value of 3,and an increasing trend at pH value of 5 and 7.(2)The HCl solutions with various concentration have different effect on mineral composition,characterized by an increase in proportion of SiO_(2) and a reduction in proportion of Na_(2)O,Al_(2)O_(3),K_(2)O,MgO,and CaO,as the solution pH value decreases.(3)After immersion in the solutions with pH values of 1,3,and 5,the tensile strength of the granite decreases by 23.85%,20.84%,and 20.24%;the average stiffness of the specimen decreases by 29.29%,23.43%,and 11.97%;the proportion of releasable energy increases by 6%,4%,and -2%;the releasable energy decreases by 54.96%,26.09%,and 14.52%;and the dissipated energy decreases by approximately 68.85%,41.39%,and 5.41%,respectively.(4)The evolution of physical and mechanical properties of the immersed granite specimen can be analyzed from a chemical aspect.The corrosive action of HCl cleaves Si–O and Al–O chemical bonds within the granite,particularly altering the tetrahedral structures of its silicate components.This process involves breaking existing chemical bonds and the formation of new ones,ultimately destroying the silicate molecular structures.As the concentration of HCl increases,the rate of these reactions accelerates,progressively weakening the chemical bonds and consequently deteriorating the mechanical characteristics of the granite.These findings can deepen our knowledge about the corrosion effect of HCI solutions on natural surrounding rocks and serve as references for further research on rock corrosion mechanisms in underground engineering.展开更多
The strength-ductility trade-off in magnesium alloys remains a critical challenge urgently requiring resolution in their engineering applications.In this study,both mechanical and corrosion properties are enhanced in ...The strength-ductility trade-off in magnesium alloys remains a critical challenge urgently requiring resolution in their engineering applications.In this study,both mechanical and corrosion properties are enhanced in extruded Mg-Y-Nd-Zr alloys by Sm addition.Sm promotes dynamic recrystallization,activates non-basal slip systems and weakens basal texture intensity,leading to the sub-grain lamellar structure and rare earth texture.The EWS2 alloy exhibits an outstanding combination of high yield strength(328 MPa)and ductility(15.1%).Furthermore,the fragmented second phases in the Sm-containing alloy are uniformly distributed,reducing the subsequent corrosion driving force after micro-galvanic corrosion and facilitating the growth of a more passivating and compact corrosion film.These combined effects contribute to the lowest degradation rate in the EWS2 alloy.This study demonstrates the correlation between microstructure and properties in Sm-containing WE series alloys,providing insights for the design of other high performance magnesium alloys.展开更多
Conventional lightweight refractory materials with low bulk density and more pores suffer from harsh corrosion and erosion in actual applications.A type of lightweight Al_(2)O_(3)-MgAl_(2)O_(4)aggregates with a core-s...Conventional lightweight refractory materials with low bulk density and more pores suffer from harsh corrosion and erosion in actual applications.A type of lightweight Al_(2)O_(3)-MgAl_(2)O_(4)aggregates with a core-shell structure was synthesized at 1750℃using a rolling granulation method.Microstructural evolution and properties of the spherical aggregates were systematically studied.Scanning electron microscope and X-ray computed tomography results confirmed that a continuous and dense MgAl_(2)O_(4)spinel shell structure with a thickness of 200-300μm was formed on the surface.The corrosion results indicated that the corrosion index of the core-shell aggregates exhibited a 60%enhancement when compared to Al_(2)O_(3)spherical.Moreover,Al_(2)O_(3)-MgAl_(2)O_(4)refractory materials,which are based on the lightweight Al_(2)O_(3)-MgAl_(2)O_(4)spherical aggregates,possessed a higher temperature modulus of rupture of 9.19 MPa,and the retention rate of residual flexural strength reached 70%after thermal shock testing.The above results showed an improvement of 129.75 and 44.28%compared with pure Al_(2)O_(3)aggregate samples,respectively.In addition,the MgAl_(2)O_(4)spinel shell could trap the Mn,Fe elements from infiltrated slag and transfer into(Mg,Fe,Mn)Al_(2)O_(4)spinel,infiltrated CaO reacts with Sample Al_(2)O_(3)matrix to form a calcium hexaluminate(CA6)isolation layer,and the above two reasons enhance the corrosion resistance of the material.The corrosion mechanism was elaborated in detail.展开更多
The corrosion wear behavior of the selective laser melting(SLM)and forged TC4 alloys in 3.5 wt.%NaCl solution is studied.Results indicate that the current densities of the two TC4 alloys increase with the increase in ...The corrosion wear behavior of the selective laser melting(SLM)and forged TC4 alloys in 3.5 wt.%NaCl solution is studied.Results indicate that the current densities of the two TC4 alloys increase with the increase in applied potential,meaning that the corrosion resistance of the alloys decreases.And the main product of the passive film is TiO_(2).What’s more,corrosion wear behavior is more severe due to the presence of corrosion,resulting in greater mass losses and deeper wear scars.To explore the interaction between corrosion and wear for the two TC4 alloys,the change of the mass loss proportions for wear caused by corrosion and corrosion caused by wear with potential is analyzed.The mass loss of wear caused by corrosion cannot be ignored,and it affects SLM TC4 alloy with the unique acicularα′-phase significantly.展开更多
Zn-Mn alloys are regarded as promising biodegradable metals for orthopedic applications owing to their moderate degradation rates and favorable osteogenic properties.However,the presence of a substantial number of sec...Zn-Mn alloys are regarded as promising biodegradable metals for orthopedic applications owing to their moderate degradation rates and favorable osteogenic properties.However,the presence of a substantial number of second-phase particles in Zn-based alloys might induce severe localized degradation via micro-coupling corrosion,thereby compromising the mechanical integrity of the alloy during in vivo tissue regeneration.In this study,high pressure solid solution(HPSS)treatment was conducted at 5 GPa and 380℃ for 1 h to fabricate Zn-0.5 Mn alloys.Microstructural characterization revealed that the HPSS treatment facilitated the formation of a supersaturated solid solution by completely dissolving theζ-MnZn_(13) phase into theα-Zn matrix.The resultant strengthening mechanisms,including supersaturated solid solution strengthening,grain-size strengthening,and dislocation strengthening,collectively enhanced the compressive yield strength(σ_(cys))of the Zn-0.5 Mn alloy to about 183.7 MPa,approximately three times that of the as-cast(AC)Zn-0.5 Mn alloy.Moreover,compared with the AC alloy,the HPSS Zn-0.5 Mn alloy exhibited uniform degradation behavior with a markedly reduced degradation rate.展开更多
Aviation aluminum alloys,primarily from the Al-Cu,Al-Zn-Mg-(Cu),and Al-Li series,have been widely applied over six decades,greatly advancing the aviation industry.However,their Corrosion Fatigue(CF)properties impede f...Aviation aluminum alloys,primarily from the Al-Cu,Al-Zn-Mg-(Cu),and Al-Li series,have been widely applied over six decades,greatly advancing the aviation industry.However,their Corrosion Fatigue(CF)properties impede further advancements,prompting extensive research into their CF behaviors and underlying mechanisms.This review comprehensively evaluates previous studies on their development history,CF mechanisms,and key influencing factors.First,the historical evolution of aerospace aluminum alloys is summarized.Then,the currently recognized four crack initiation mechanisms and three crack propagation mechanisms are concluded,and the effects of external and internal factors on CF performance are discussed.The paper also reviews three methods and CF life prediction models for characterizing the CF behavior of aerospace aluminum alloys.Most existing studies on the CF behavior of aluminum alloys are based on the single corrosive environment,neglecting the fact that aircrafts experience multiple corrosive environments during service.However,the most critical scientific challenge is how to enhance their CF properties under increasingly demanding service conditions.For the purpose,this paper introduces advanced forming techniques based on the microstructural control,such as Equal Channel Angular Pressing(ECAP)and High-Pressure Torsion(HPT),aimed at laying the theoretical foundation for improving CF properties through microstructural regulation.展开更多
The mining industry is frequently subjected to various disasters,one of the major concerns is water-related disasters,particularly seam floor water inrush.These disasters pose significant threats to the safety and pro...The mining industry is frequently subjected to various disasters,one of the major concerns is water-related disasters,particularly seam floor water inrush.These disasters pose significant threats to the safety and production of deep coal mines.The primary reason for this is that the fracturing of the rock mass induces the formation of a fluid(water)with both kinetic and potential energy.In this paper,a novel water inrush mechanism for deep floor failure due to water hammer effects is proposed based on the Xingdong coal mine in China.The water hammer pressure within rock pore channels has a different impact on the surrounding rock,leading to the degradation of the rock mass channel through repeated conduction and instantaneous cutoff.To further investigate this phenomenon,a progressive corrosion fracture mechanics(PCFM)model induced by a water hammer is established.The results show that the water hammer pressure caused by instantaneous channel truncation increases with increasing water flow velocity.The chemical damage factor(i.e.,stress corrosion fracture)is also incorporated into the Dugdale-Barenblatt(D-B)model to analyze the factors influencing the PCFM.These findings indicate that the greater the degree of damage is,the more likely the concealed fault is to experience water inrush.Finally,methods for controlling water inrush caused by the water hammer effects of deep floors are proposed.The failure mechanisms of the water hammer and the PCFM provide theoretical and practical guidance for controlling water inrush from the deep floor.展开更多
To quantify the acid corrosion characteristics and shear creep behavior of carbonaceous shale under acid corrosion,immersion tests and acid corrosion shear creep tests were conducted at different pH values.The shear f...To quantify the acid corrosion characteristics and shear creep behavior of carbonaceous shale under acid corrosion,immersion tests and acid corrosion shear creep tests were conducted at different pH values.The shear fracture surface characteristics of the damaged samples were observed using scanning electron microscopy(SEM).The mechanisms of acid corrosion and its shear creep effects on carbonaceous shale were elucidated.The results indicate that the higher the initial concentration of H+,the greater the wave velocity degradation rate and mass damage rate of the sample after acid etching reaction.The mass damage rate,wave velocity degradation rate of carbonaceous shale,and the pH of the solution first increased linearly and rapidly with time,followed by a nonlinear decrease,and finally reached a stable state.When the number of dry-wet cycles is constant,the higher the H+concentration,the greater the creep deformation,the longer the decelerating creep time,the higher the steady-state creep rate,and the lower the long-term strength.Acid corrosion induces mineral dissolution,increasing pore density.The products of acid corrosion reactions and clay minerals migrate and precipitate along paths influenced by dry-wet cycles,resulting in overall structural damage and decreased mechanical strength in carbonaceous shale.展开更多
A calcium zirconate crucible material with excellent performance was prepared by fixing the particle size proportion and exploring the addition of Y_(2)O_(3).The results show that Y^(3+)solid-dissolves into c-ZrO_(2)t...A calcium zirconate crucible material with excellent performance was prepared by fixing the particle size proportion and exploring the addition of Y_(2)O_(3).The results show that Y^(3+)solid-dissolves into c-ZrO_(2)to occupy the Zr^(4+)positions,leading to structural defects and promoting the sintering of calcium zirconate.Adding 0.5 wt.%Y_(2)O_(3)into calcium zirconate can enhance the modulus of rupture,reduce the thermal expansion coefficient,and improve the thermal shock resistance.Through high-temperature test,it is found that adding 0.5 wt.%Y_(2)O_(3)significantly improves the corrosion resistance of the sample.展开更多
基金financial support of the National Natural Science Foundation of China(Nos.U21A2058 and 52272071)Hubei Provincial Natural Science Foundation of China(No.2025AFA066)Hubei Provincial Special Fund for Central-Guided Local S&T Development(No.2025CSA017).
文摘MgO–C refractories are extensively employed in critical metallurgical equipment such as converters, electric arc furnaces and ladles, valued for their exceptional thermal shock resistance and slag corrosion resistance. However, the use of high-proportion scrap steel in low-carbon steelmaking processes accelerates the corrosive degradation of MgO–C refractories due to changes in slag basicity and viscosity. Enhancing the slag corrosion resistance of MgO–C refractories has thus become an urgent priority. The methods for evaluating the slag corrosion resistance of MgO–C refractories are systematically reviewed, the slag corrosion mechanisms are elucidated, and various strategies and recent advances for enhancing their slag corrosion resistance are summarized. The aim is to provide valuable insights and references for ongoing research in this field while outlining potential directions for future studies.
基金Gansu Provincial Science and Technology Major Special Program(24ZDWA008)Fourth Batch of Top Leading Talents Fund Projects in Gansu Province(ZZ2023G50100013)。
文摘In this study,FeCr_(x)MnAlCu(x=0,0.5,1.0,1.5,2.0)high-entropy alloys were fabricated using vacuum arc melting,and the corrosion behavior of these alloys in 3.5wt%NaCl solution at room temperature was investigated by electrochemical dynamic potential polarization curves and immersion experiments.The microstructure results show that the high-entropy alloy with x=0 has a body-centered cubic phase structure,whereas the high-entropy alloys with x=0.5–2.0 have a mixed face-centered cubic+body-centered cubic dual-phase structure.The corrosion results show that the corrosion resistance of the high-entropy alloy is increased with the increase in Cr content.Among them,the high-entropy alloy with x=2.0 exhibits the optimal corrosion resistance:the highest self-corrosion potential(E_(corr)=−0.354 V vs.Ag/AgCl),the smallest self-corrosion current density(I_(corr)=1.991×10^(−6)A·cm^(−2)),and the smallest corrosion rate(0.0292 mm/a).The composite passivation film of oxides and hydroxides is formed on the surface of the corroded high-entropy alloys,and the Cr_(2)O_(3)content is increased with the increase in Cr content,which effectively improves the stability and protective properties of the passivation film.
文摘The J55 tubing thread fastener in an electric pump well experienced corrosion failure.The causes of the failure were investigated through physical and chemical property tests,corrosion product analysis,and microbial analysis.The results show that the metallographic structure and composition of the J55 tubing were normal.CO 2 corrosion was not the main cause of the thread fastener failure.The actual cause of the corrosion failure was microbiological corrosion,such as sulfate-reducing bacteria,thiosulfate-reducing bacteria,and iron-oxidizing bacteria.
基金sponsored by the National Natural Science Foundation of China(52302039,52301043)the Guangdong Basic and Applied Basic Research Foundation(2024A1515240056)+3 种基金the Shenzhen Science and Technology Program(GXWD20231129113217001)the Shenzhen Key Laboratory of New Materials Technology(SYSPG20241211173609003)the Postdoctoral Research Startup Expenses of Shenzhen(NA25501001)Shenzhen Introduce High-level Talents and Scientific Research Start-up Funds(NA11409005)。
文摘Seawater electrolysis has been explored as a viable and sustainable method for green hydrogen production in regions characterized by freshwater scarcity but abundant renewable energy resources.However,the high concentration of chlorine ions(Cl^(-))in seawater leads to severe corrosion of metallic electrodes,which significantly challenges the stability of electrode catalysts in seawater electrolysis.Owing to the Cl^(-)corrosion and the competitive oxygen/chlorine evolution reactions,the design of durable and active anode catalysts is key to achieving practical seawater electrolysis.To address this challenge,this review systematically analyzes the chlorine-induced corrosion mechanisms of anode catalysts,evaluates various anticorrosion strategies,and explores future prospects for enhancing anode durability.Three mainstream anticorrosion strategies are summarized and assessed for their effectiveness in mitigating the chlorineinduced damage to anode catalysts:the physical surface coatings,electrostatic repulsion,and Cl^(-)adsorption regulation.In addition,some emerging strategies are further introduced to highlight the future trends of state-of-the-art techniques for seawater electrolysis.This review aims to provide novel insights and practical guidance for developing more stable and efficient anode catalysts for hydrogen production via seawater electrolvsis.
基金supported by the National Natural Science Foundation of China(Grant Nos.U22A20106,52201112,and U22A20173)Fundamental Research Funds for the Central Universities(N25LJ002).
文摘Coating-free press-hardened steel(CF-PHS)had effectively tackled the challenge of high-temperature oxidation during processing through Cr-Si alloying strategy.However,it is equally essential to investigate its corrosion resistance and the role of the oxide scale in corrosion environments.The corrosion resistance of CF-PHS with and without oxide scale was comprehensively evaluated by analyzing electrochemical processes and corrosion products,as well as characterizing the corroded oxide scale features,while comparing it with commercial 22MnB5 steel.The results indicate that CF-PHS exhibits superior corrosion resistance compared to 22MnB5 steel and the presence of oxide scale may have a negative influence on short-time corrosion resistance.The ultra-thin oxide scale is unable to effectively and timely mitigate pit propagation during the rapid electrochemical tests.Conversely,during the prolonged corrosion process,the oxide scale can still function as the physical barrier to provide protective effects,making the corrosion process develop more slowly and evenly.
基金financially supported by the National Natural Science Foundation of China(Nos.52104319 and 52374323)。
文摘This study utilizes wet/dry cyclic corrosion testing combined with corrosion big data technology to investigate the mechanism by which chloride ions(Cl^(-))influence the corrosion behavior of 650 MPa high-strength low-alloy(HSLA)steel in industrially polluted environments.The corrosion process of 650 MPa HSLA steel occurred in two distinct stages:an initial corrosion stage and a stable corrosion stage.During the initial phase,the weight loss rate increased rapidly owing to the instability of the rust layer.Notably,this study demonstrated that 650 MPa HSLA steel exhibited superior corrosion resistance in Cl-containing environments.The formation of a corrosion-product film eventually reduced the weight-loss rate.However,the intrusion of Cl^(-)at increasing concentrations gradually destabilized theα/γ^(*)phases of the rust layer,leading to a looser structure and lower polarization resistance(R_(p)).The application of corrosion big data technology in this study facilitated the validation and analysis of the experimental results,offering new insights into the corrosion mechanisms of HSLA steel in chloride-rich environments.
文摘High-purity graphite is extensively utilized in the semiconductor industry.Enhancing its corrosion resistance is crucial for reducing the manufacturing costs of the third-generation semiconductors.In this study,a continuous and dense TaC coating was fabricated on the surface of graphite using CVD method.The corrosion resistance and mechanism of the coating were investigated in a high-temperature steam environment.This environment involved temperatures exceeding 2200 K and the erosion of the coating by Si-containing mixed steam flows.The results indicated that the corrosion in the affected areas was primarily due to chemical reactions,characterized by the formation of pores and micro-cracks,whereas failure areas were dominated by mechanical delamination,which led to macroscopic defects.Moreover,the mixed high-temperature steam corrosion of the TaC coating showed preferential selectivity,resulting in a stepped corrosion morphology at the crystalline level.The surface roughness of the samples significantly increased after corrosion,from 0.36 to 5.28μm,although the surface composition remained largely unchanged.The TaC coating provides a certain level of protection to the graphite substrate,enhancing the service life of graphite components and demonstrating promising application potential.
基金Tianjin Municipal Natural Science Foundation(23JCYBJC00040)National Natural Science Foundation of China(52175369)。
文摘The TiB+TiC dual-reinforced B_(4)C/TC4 composite was in-situ fabricated via incorporating 0.5wt%B_(4)C reinforcement during the laser melting deposition process.Different heat treatments of annealing and solid solution were used to regulate the microstructure,mechanical properties,and corrosion properties of B_(4)C/TC4 composite.Results show that with the increase in temperature from 500℃to 800°C,partial lamellarα-Ti in the as-deposited sample is gradually transformed into equiaxedα-Ti,accompanied by the disappearance of basketweave microstructure.At 1100°C,a small portion of TiC phase suffers fusion.This composite exhibits the optimal combination of strength and plasticity after annealing at 500℃for 4 h followed by furnace cooling,which is attributed to the stress release effect and the refined basketweave microstructure.However,this composite shows a decline in corrosion resistance after various heat treatments due to grain coarsening and micro-galvanic corrosion.
基金supported by the Shandong Provincial Natural Science Foundation(No.ZR2022ME052)the National Natural Science Foundation of China(No.22404153)+4 种基金the TaiShan Scholars of Shandong China(No.tsqn202306113 and tsqn202408081)the Excellent Youth Science Fund Project of Shandong China(No.2025HWYQ-032)the China Postdoctoral Science Foundation(No.2024M753044)the Postdoctoral Fellowship Program of CPSF(No.GZB20240693)the Natural Science Foundation of Qingdao(No.24-4-4-zrjj-9-jch)。
文摘Photoelectrochemical seawater splitting is promising for renewable hydrogen,yet severe chloride corrosion remains a roadblock.Although amorphous catalysts improve hematite(α-Fe_(2)O_(3))photoanode activity,their defect-enabled functionality inherently accelerates structural degradation,exacerbating chloride-induced corrosion.Here,a synergistic dual-functional nano-armor is designed by anchoring phosphate(PO_(4)^(3-))to active sites on amorphous NiMoO_(4)(a-NiMoO_(4)@PO_(4)^(3-)),achieving dual activitystability enhancement.Detailed physicochemical characterization and density functional theory(DFT)calculations show that the successful and stable anchoring of phosphate is highly dependent on the amorphous structural properties of a-NiMoO_(4).Its rich disordered coordination environment provides sufficient highly reactive sites,allowing PO_(4)^(3-)to be firmly bound through strong coordination bonds,which is the key for the dual role of PO_(4)^(3-)coordination.As a dynamic Cl-shield,PO_(4)^(3-)coordinates unsaturated Ni sites,forming an anionic layer that resists Cl-via steric-electrostatic blocking.As an electronic modulator,PO_(4)^(3-)triggers metal-to-ligand charge transfer at Ni sites,depleting electron density to optimize the intermediate adsorption of oxygen evolution reaction(OER)and reduce kinetic barriers.Simultaneously,this charge redistribution induces a built-in electric field that accelerates holeselective transport.Benefiting from these dual effects,the Fe_(2)O_(3)/a-NiMoO_(4)@PO_(4)^(3-)achieves 4 mA cm^(-2)at 1.23 V_(RHE) with exceptional stability in seawater.This work leverages the unique coordination flexibility of amorphous structures to construct a phosphate-coordinated bifunctional nano-armor on hematite photoanodes,which simultaneously enables efficient chloride exclusion and electronic structure optimization.The synergistic mechanism,rooted in strong phosphate anchoring on amorphous carriers,establishes a new design paradigm for photoelectrochemical systems that integrate high activity with extreme environmental stability,providing an efficient pathway toward corrosion-resistant seawater splitting.
基金supported by the National Natural Science Foundation of China(12522203,12532003 and U2267252)National Technological Basic Research Program of China,the Development and Application Project of Ship CAE Softwarethe Science and Technology Innovation 2035 Major Project of Yongjiang under Grant(2025Z009).
文摘The synergistic effects of corrosion and impact loading on the microstructure evolution and dynamic mechanical properties of ultrahigh-strength AerMet 100 steel are investigated.Through integrated experiments and modeling,the result reveals that the corrosion leads to grain refinement and a reduction in the proportion of low-angle grain boundaries.Notably,corrosion promotes austenite enrichment(increasing from 1.8%to 13.9%)through selective dissolution of the martensitic matrix,while repetitive impacts reverse this trend(reducing to 0.1%)through stress-induced martensitic transformation.Fracture analysis demonstrates corrosion-induced ductile-to-brittle transition,with quasi-cleavage features dominating after prolonged corrosion.A physics-based dynamic yield strength model with<3%prediction error relative to impact tests is developed.These findings establish microstructure-property relationships of AerMet 100 steel under multi-field coupling,providing critical guidance for designing corrosion-resistant ultrahigh-strength steels in marine-impact environments.
基金supported by the Science and Technology Major Project of Liaoning province(2024JH1/11700034)the funds of Liaoning BaiQianWan Talents Programthe Innovation Fund of Institute of Metal Research(IMR),Chinese Academy of Sciences(CAS).
文摘Through investigating the influence of electrochemically charged hydrogen on microstructural damage and corrosion performance of an as-cast Ti-6Al-4V(in wt.%)alloy,it demonstrated that after being performed hydrogen-charging for 4 h at an applied current density value of 50 mA/cm^(2),micro cracks were preferentially presented in α-Ti phase and at interfaces between α-Ti and β-Ti phases.Moreover,the quantity of cracks increased with extending the hydrogen-charging time.Failure analysis demonstrated that micro cracks were caused by the formation of needle-like δ-TiH2 hydride.For 4 h-charged sample,all of the exposed α-Ti phase can be changed into hydrides,resulting in the formation of a layer of hydride with the thickness value of 5μm.After hydrogen-charging for 8 and 16 h,the thicknesses values of formed hydride layers were 8 and 18μm,respectively.Due to anodic dissolution of hydrides,the corrosion resistance of charged samples was degraded.The determined current density values of the uncharged,4 h-charged,8 h-charged and 16 h-charged samples were 34.7,42.3,50.7 and 63.4 nA/cm^(2),respectively.
基金National Science Fund for Distinguished Young Scholars,Grant/Award Number:52225403State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering,Grant/Award Number:SDGZK2404Fundamental Research Funds for the Central Universities,Grant/Award Number:2023KYJD1006。
文摘Hydrochloric acid(HCl)extensively exists in deep underground projects,arising from the transportation of industrial raw materials or fracturing fluids of petroleum engineering.It results in corrosion,which can significantly impact the stability of surrounding rock structures.Therefore,in-depth analysis of the degradation of rock corroded by the HCl solution is an essential task for underground engineering.In this study,the granite specimens are initially treated with the HCl solution with various concentrations.Then,the tests and analyses,such as electrical conductivity(EC)measurements,mineral composition assays,and Brazilian splitting tests,are employed to investigate the corrosion mechanism of the HCl solution.Our results and findings are generally as follows:(1)As the immersion time increases,the EC exhibits a relatively high level at pH value of 1,a decreasing trend at pH value of 3,and an increasing trend at pH value of 5 and 7.(2)The HCl solutions with various concentration have different effect on mineral composition,characterized by an increase in proportion of SiO_(2) and a reduction in proportion of Na_(2)O,Al_(2)O_(3),K_(2)O,MgO,and CaO,as the solution pH value decreases.(3)After immersion in the solutions with pH values of 1,3,and 5,the tensile strength of the granite decreases by 23.85%,20.84%,and 20.24%;the average stiffness of the specimen decreases by 29.29%,23.43%,and 11.97%;the proportion of releasable energy increases by 6%,4%,and -2%;the releasable energy decreases by 54.96%,26.09%,and 14.52%;and the dissipated energy decreases by approximately 68.85%,41.39%,and 5.41%,respectively.(4)The evolution of physical and mechanical properties of the immersed granite specimen can be analyzed from a chemical aspect.The corrosive action of HCl cleaves Si–O and Al–O chemical bonds within the granite,particularly altering the tetrahedral structures of its silicate components.This process involves breaking existing chemical bonds and the formation of new ones,ultimately destroying the silicate molecular structures.As the concentration of HCl increases,the rate of these reactions accelerates,progressively weakening the chemical bonds and consequently deteriorating the mechanical characteristics of the granite.These findings can deepen our knowledge about the corrosion effect of HCI solutions on natural surrounding rocks and serve as references for further research on rock corrosion mechanisms in underground engineering.
基金supported by the National Natural Science Foundation of China(Nos.52201119,52371108)Frontier Exploration Project of Longmen Laboratory,China(No.LMQYTSKT014)The Joint Fund of Henan Science and Technology R&D Plan of China(No.242103810056).
文摘The strength-ductility trade-off in magnesium alloys remains a critical challenge urgently requiring resolution in their engineering applications.In this study,both mechanical and corrosion properties are enhanced in extruded Mg-Y-Nd-Zr alloys by Sm addition.Sm promotes dynamic recrystallization,activates non-basal slip systems and weakens basal texture intensity,leading to the sub-grain lamellar structure and rare earth texture.The EWS2 alloy exhibits an outstanding combination of high yield strength(328 MPa)and ductility(15.1%).Furthermore,the fragmented second phases in the Sm-containing alloy are uniformly distributed,reducing the subsequent corrosion driving force after micro-galvanic corrosion and facilitating the growth of a more passivating and compact corrosion film.These combined effects contribute to the lowest degradation rate in the EWS2 alloy.This study demonstrates the correlation between microstructure and properties in Sm-containing WE series alloys,providing insights for the design of other high performance magnesium alloys.
基金funded by the Key Project of the National Natural Science Foundation of China(Grant No.U21A2058)Research Project of Hubei Provincial Department of Science and Technology(2024CSA075)support from the Taizhou Fengcheng Talent Program(2024).
文摘Conventional lightweight refractory materials with low bulk density and more pores suffer from harsh corrosion and erosion in actual applications.A type of lightweight Al_(2)O_(3)-MgAl_(2)O_(4)aggregates with a core-shell structure was synthesized at 1750℃using a rolling granulation method.Microstructural evolution and properties of the spherical aggregates were systematically studied.Scanning electron microscope and X-ray computed tomography results confirmed that a continuous and dense MgAl_(2)O_(4)spinel shell structure with a thickness of 200-300μm was formed on the surface.The corrosion results indicated that the corrosion index of the core-shell aggregates exhibited a 60%enhancement when compared to Al_(2)O_(3)spherical.Moreover,Al_(2)O_(3)-MgAl_(2)O_(4)refractory materials,which are based on the lightweight Al_(2)O_(3)-MgAl_(2)O_(4)spherical aggregates,possessed a higher temperature modulus of rupture of 9.19 MPa,and the retention rate of residual flexural strength reached 70%after thermal shock testing.The above results showed an improvement of 129.75 and 44.28%compared with pure Al_(2)O_(3)aggregate samples,respectively.In addition,the MgAl_(2)O_(4)spinel shell could trap the Mn,Fe elements from infiltrated slag and transfer into(Mg,Fe,Mn)Al_(2)O_(4)spinel,infiltrated CaO reacts with Sample Al_(2)O_(3)matrix to form a calcium hexaluminate(CA6)isolation layer,and the above two reasons enhance the corrosion resistance of the material.The corrosion mechanism was elaborated in detail.
基金supported by the National Natural Science Foundation of China(No.52001142)Young Elite Scientists Sponsorship Program by CAST(No.2022QNRC001).
文摘The corrosion wear behavior of the selective laser melting(SLM)and forged TC4 alloys in 3.5 wt.%NaCl solution is studied.Results indicate that the current densities of the two TC4 alloys increase with the increase in applied potential,meaning that the corrosion resistance of the alloys decreases.And the main product of the passive film is TiO_(2).What’s more,corrosion wear behavior is more severe due to the presence of corrosion,resulting in greater mass losses and deeper wear scars.To explore the interaction between corrosion and wear for the two TC4 alloys,the change of the mass loss proportions for wear caused by corrosion and corrosion caused by wear with potential is analyzed.The mass loss of wear caused by corrosion cannot be ignored,and it affects SLM TC4 alloy with the unique acicularα′-phase significantly.
基金Project(52401064)supported by the National Natural Science Foundation of ChinaProject(24B0172)supported by the Scientific Research Fund of Hunan Provincial Education Department,ChinaProject(XDCX2024Y273)supported by the Postgraduate Scientific Research Innovation Project of Xiangtan University,China。
文摘Zn-Mn alloys are regarded as promising biodegradable metals for orthopedic applications owing to their moderate degradation rates and favorable osteogenic properties.However,the presence of a substantial number of second-phase particles in Zn-based alloys might induce severe localized degradation via micro-coupling corrosion,thereby compromising the mechanical integrity of the alloy during in vivo tissue regeneration.In this study,high pressure solid solution(HPSS)treatment was conducted at 5 GPa and 380℃ for 1 h to fabricate Zn-0.5 Mn alloys.Microstructural characterization revealed that the HPSS treatment facilitated the formation of a supersaturated solid solution by completely dissolving theζ-MnZn_(13) phase into theα-Zn matrix.The resultant strengthening mechanisms,including supersaturated solid solution strengthening,grain-size strengthening,and dislocation strengthening,collectively enhanced the compressive yield strength(σ_(cys))of the Zn-0.5 Mn alloy to about 183.7 MPa,approximately three times that of the as-cast(AC)Zn-0.5 Mn alloy.Moreover,compared with the AC alloy,the HPSS Zn-0.5 Mn alloy exhibited uniform degradation behavior with a markedly reduced degradation rate.
基金co-supported by the National Natural Science Foundation of China(Nos 52475346 and U21A20130)the Natural Science Foundation of Hunan Province,China(No.2023JJ10019)+1 种基金China Postdoctoral Science Foundation(No.2022M712642)Hunan Science and Technology Innovation Plan,China(2023RC1068)。
文摘Aviation aluminum alloys,primarily from the Al-Cu,Al-Zn-Mg-(Cu),and Al-Li series,have been widely applied over six decades,greatly advancing the aviation industry.However,their Corrosion Fatigue(CF)properties impede further advancements,prompting extensive research into their CF behaviors and underlying mechanisms.This review comprehensively evaluates previous studies on their development history,CF mechanisms,and key influencing factors.First,the historical evolution of aerospace aluminum alloys is summarized.Then,the currently recognized four crack initiation mechanisms and three crack propagation mechanisms are concluded,and the effects of external and internal factors on CF performance are discussed.The paper also reviews three methods and CF life prediction models for characterizing the CF behavior of aerospace aluminum alloys.Most existing studies on the CF behavior of aluminum alloys are based on the single corrosive environment,neglecting the fact that aircrafts experience multiple corrosive environments during service.However,the most critical scientific challenge is how to enhance their CF properties under increasingly demanding service conditions.For the purpose,this paper introduces advanced forming techniques based on the microstructural control,such as Equal Channel Angular Pressing(ECAP)and High-Pressure Torsion(HPT),aimed at laying the theoretical foundation for improving CF properties through microstructural regulation.
基金supported by the National Natural Science Foundation of China(Grant Nos.52225404 and 52404121)the Key Research and Development Program Projects of Xinjiang Uygur Autonomous Region(Grant No.2024B03017).
文摘The mining industry is frequently subjected to various disasters,one of the major concerns is water-related disasters,particularly seam floor water inrush.These disasters pose significant threats to the safety and production of deep coal mines.The primary reason for this is that the fracturing of the rock mass induces the formation of a fluid(water)with both kinetic and potential energy.In this paper,a novel water inrush mechanism for deep floor failure due to water hammer effects is proposed based on the Xingdong coal mine in China.The water hammer pressure within rock pore channels has a different impact on the surrounding rock,leading to the degradation of the rock mass channel through repeated conduction and instantaneous cutoff.To further investigate this phenomenon,a progressive corrosion fracture mechanics(PCFM)model induced by a water hammer is established.The results show that the water hammer pressure caused by instantaneous channel truncation increases with increasing water flow velocity.The chemical damage factor(i.e.,stress corrosion fracture)is also incorporated into the Dugdale-Barenblatt(D-B)model to analyze the factors influencing the PCFM.These findings indicate that the greater the degree of damage is,the more likely the concealed fault is to experience water inrush.Finally,methods for controlling water inrush caused by the water hammer effects of deep floors are proposed.The failure mechanisms of the water hammer and the PCFM provide theoretical and practical guidance for controlling water inrush from the deep floor.
基金supported by the National Natural Science Foundation of China(Grant Nos.42307252 and U1802243)the Technology Projects of WUST(Wuhan University of Science and Technology)Cultivate Innovation Teams(Grant No.2018TDX01).
文摘To quantify the acid corrosion characteristics and shear creep behavior of carbonaceous shale under acid corrosion,immersion tests and acid corrosion shear creep tests were conducted at different pH values.The shear fracture surface characteristics of the damaged samples were observed using scanning electron microscopy(SEM).The mechanisms of acid corrosion and its shear creep effects on carbonaceous shale were elucidated.The results indicate that the higher the initial concentration of H+,the greater the wave velocity degradation rate and mass damage rate of the sample after acid etching reaction.The mass damage rate,wave velocity degradation rate of carbonaceous shale,and the pH of the solution first increased linearly and rapidly with time,followed by a nonlinear decrease,and finally reached a stable state.When the number of dry-wet cycles is constant,the higher the H+concentration,the greater the creep deformation,the longer the decelerating creep time,the higher the steady-state creep rate,and the lower the long-term strength.Acid corrosion induces mineral dissolution,increasing pore density.The products of acid corrosion reactions and clay minerals migrate and precipitate along paths influenced by dry-wet cycles,resulting in overall structural damage and decreased mechanical strength in carbonaceous shale.
基金provided by the National Natural Science Foundation of China(NSFC)through the Joint Fund Project(No.U24A202815)the Youth Science Fund Project(No.52302031).
文摘A calcium zirconate crucible material with excellent performance was prepared by fixing the particle size proportion and exploring the addition of Y_(2)O_(3).The results show that Y^(3+)solid-dissolves into c-ZrO_(2)to occupy the Zr^(4+)positions,leading to structural defects and promoting the sintering of calcium zirconate.Adding 0.5 wt.%Y_(2)O_(3)into calcium zirconate can enhance the modulus of rupture,reduce the thermal expansion coefficient,and improve the thermal shock resistance.Through high-temperature test,it is found that adding 0.5 wt.%Y_(2)O_(3)significantly improves the corrosion resistance of the sample.
