Most of the so-called Bayan Obo fine-grained dolomite marbles collected from the main and east orebodies show a microporphyritic texture,namely the microphenocrysts are set in a very finegrained matrix,although nearly...Most of the so-called Bayan Obo fine-grained dolomite marbles collected from the main and east orebodies show a microporphyritic texture,namely the microphenocrysts are set in a very finegrained matrix,although nearly all of them have undergone recrystallization caused either by deformation or alteration.The texture seems likely to have maintained the original features.It is known that one of the most characteristic textures of volcanic rocks is the porphyritic texture,and the microporphyritic texture is a variety in which both the phenocrysts and the matrix are only distinguishable with the microscope.Therefore,the dolomite marbles in the main and east orebodies may be related to the extrusive carbonatites.In addition,there also occur some carbonatite sills and dykes with different textures at Bayan Obo.Thus,the Bayan Obo carbonatites are polyphase intrusive and extrusive carbonatites.展开更多
Ultra-high-strength aluminumalloy profile is an ideal choice for aerospace structuralmaterials due to its excellent specific strength and corrosion resistance.However,issues such as uneven metal flow,stress concentrat...Ultra-high-strength aluminumalloy profile is an ideal choice for aerospace structuralmaterials due to its excellent specific strength and corrosion resistance.However,issues such as uneven metal flow,stress concentration,and forming defects are prone to occur during their extrusion.This study focuses on an Al-Zn-Mg-Cu ultra-high-strength aluminum alloy profile with a double-U,multi-cavity thin-walled structure.Firstly,hot compression experiments were conducted at temperatures of 350○C,400○C,and 450○C,with strain rates of 0.01 and 1.0 s^(−1),to investigate the plastic deformation behavior of the material.Subsequently,a 3D coupled thermo-mechanical extrusion simulation model was established using Deform-3D to systematically analyze the influence of die structure and process parameters on metal flow velocity,effective stress/strain,and temperature distribution.The simulation revealed significant velocity differences,stress concentration,and uneven temperature distribution.Key parameters,including mesh density,extrusion ratio,die fillet,and bearing length,were optimized through full-factorial experiments.This optimization,combined with a stepped flow-guiding die design,effectively improved the metal flow pattern during extrusion.Trial production based on both the initial and optimized parameters were carried out.A comparative analysis demonstrates that the optimized scheme results in a final profile whose cross-section matches the target design closely,with complete filling of complex features and no obvious forming defects.This research provides a valuable reference for the extrusion process optimization and die design of complex-section profiles made from ultra-high-strength aluminum alloys.展开更多
Fibre Extrusion Technology Ltd(FET)of Leeds,UK reported another successful exhibition at COMPAMED 2025 in Dusseldorf,following closely on the heels of ITMA ASIA in Singapore.This was the second time that FET had exhib...Fibre Extrusion Technology Ltd(FET)of Leeds,UK reported another successful exhibition at COMPAMED 2025 in Dusseldorf,following closely on the heels of ITMA ASIA in Singapore.This was the second time that FET had exhibited at this leading international trade fair for the medical technology supplier sector,a reflection of the company’s growing role in this sector.More than half of FET’s turnover is currently derived from the burgeoning medical market.COMPAMED is aimed at suppliers of a wide range of high-quality medical technology components,services and production equipment for the medical industry.FET’s expanding role in the medical sector is therefore an ideal fit for this trade show.展开更多
The composite material layering process has attracted considerable attention due to its production advantages,including high scalability and compatibility with a wide range of raw materials.However,changes in process ...The composite material layering process has attracted considerable attention due to its production advantages,including high scalability and compatibility with a wide range of raw materials.However,changes in process conditions can lead to degradation in layer quality and non-uniformity,highlighting the need for real-time monitoring to improve overall quality and efficiency.In this study,an AI-based monitoring system was developed to evaluate layer width and assess quality in real time.Three deep learning models Faster Region-based Convolutional Neural Network(R-CNN),You Only Look Once version 8(YOLOv8),and Single Shot MultiBox Detector(SSD)were compared,and YOLOv8 was ultimately selected for its superior speed,flexibility,and scalability.The selected model was integrated into a user-friendly interface.To verify the reliability of the system,bead width control experiments were conducted,which identified feed speed and extrusion speed as the key process parameters.Accordingly,a Central Composite Design(CCD)experimental plan with 13 conditions was applied to evaluate layer width and validate the system’s reliability.Finally,the proposed system was applied to the additive manufacturing of an aerospace component,where it successfully detected bead width deviations during printing and enabled stable fabrication with a maximum geometric deviation of approximately 6 mm.These findings demonstrate the critical role of real-time monitoring of layer width and quality in improving process stability and final product quality in composite material additive manufacturing.展开更多
In this study,we investigated the effect of high-solubility wheat gluten proteins(hs-WGP) prepared by pH-cycle treatment on soybean isolate-based extrudates.The results showed that the addition of hs-WGP can improve t...In this study,we investigated the effect of high-solubility wheat gluten proteins(hs-WGP) prepared by pH-cycle treatment on soybean isolate-based extrudates.The results showed that the addition of hs-WGP can improve textural properties of soybean isolate-based extrudate via regulating the hardness to appropriate range.At molecular level,it was further found that the hs-WGP was cross-linked with soy protein isolate mainly through hydrogen bonding and disulfide bonding,and the spherical protein of soy protein isolate was wrapped by the hs-WGP,which weakened the thermal unfolding of globular proteins during heating process,reduced the degree of heat-curing gel,resulted in a reduction in hardness.In addition,hs-WGP/soybean protein composite extrudates possessed a more balanced amino acid composition,which have a positive impact on meat analogues at the nutritional level.展开更多
Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusi...Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed slightly.The dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)increased.With the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical<2111>-<1123>rare-earth(RE)textures.The alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening contributions.These results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.展开更多
The microstructures and mechanical properties of Al-8.3Zn-3.3Cu-2.2Mg alloys prepared via hot extrusion and liquid forging methods were investigated.Results show that based on DEFORM simulation analysis,the optimal ho...The microstructures and mechanical properties of Al-8.3Zn-3.3Cu-2.2Mg alloys prepared via hot extrusion and liquid forging methods were investigated.Results show that based on DEFORM simulation analysis,the optimal hot extrusion parameters are determined as ingot initial temperature of 380°C and extrusion speed of 3 mm/s.The hot-extruded aluminum alloy after T6 heat treatment presents superior mechanical properties with yield strength of 519.6 MPa,ultimate tensile strength of 582.1 MPa,and elongation of 11.0%.Compared with the properties of gravity-cast and liquid-forged alloys,the yield strength of hot-extruded alloy increases by 30.8%and 4.9%,and the ultimate tensile strength improves by 43.5%and 10.2%,respectively.The significant improvement in tensile strength of the hot-extruded alloys is attributed to the elimination of casting defects and the refinement of matrix grain and eutectic phases.In addition,the hot-extruded alloy demonstrates superior plasticity compared with the liquid-forged alloy.This is because severe plastic deformation occurs during hot extrusion,which effectively breaks and disperses the eutectic phases,facilitating the dissolution and precipitation of the second phases and inhibiting the microcrack initiation.展开更多
This study compares the microstructural evolution,dynamic recrystallization(DRX)behavior,tensile properties,and age-hardenability between the newly developed high-speed-extrudable BA56 alloy and those of the widely re...This study compares the microstructural evolution,dynamic recrystallization(DRX)behavior,tensile properties,and age-hardenability between the newly developed high-speed-extrudable BA56 alloy and those of the widely recognized AZ31 alloy in industry.Unlike the AZ31 alloy,which retains partially unrecrystallized grains,the high-speed-extruded BA56 alloy demonstrates a coarser but entirely recrystallized and more homogeneous microstructure.The fine-grained structure and abundant Mg_(3)Bi_(2) particles in the BA56 extrusion billet significantly enhance its DRX behavior,thus enabling rapid and complete recrystallization during extrusion.The BA56 alloy contains band-like fragmented Mg_(3)Bi_(2) particles and numerous fine Mg_(3)Bi_(2) particles distributed throughout the material,in contrast to the sparse Al_(8)Mn_(5) particles in the AZ31 alloy.These features contribute to superior mechanical properties of the BA56 alloy,which achieves tensile yield and ultimate tensile strengths of 205 and 292 MPa,respectively,compared to 196 and 270 MPa for the AZ31 alloy.The superior strength of the BA56 alloy,even with its coarser grain size,can be explained by its elevated Hall-Petch constant and the strengthening contribution from the fine Mg_(3)Bi_(2) particles.Additionally,the BA56 alloy demonstrates significant age-hardenability,achieving a 22%enhancement in hardness following T5 aging,attributed to the precipitation of nanoscale Mg_(3)Bi_(2) and Mg_(17)Al_(12) phases.By contrast,the AZ31 alloy shows minimal hardening due to the absence of precipitate formation during aging.These findings suggest that the BA56 alloy is a promising candidate for the production of extruded Mg components requiring a combination of high productivity,superior mechanical performance,and wide-ranging process adaptability.展开更多
Fabricating Mg/Al laminate is an effective strategy to circumvent the inherently low formability and poor corrosion resistance of Mg alloys.Here,Mg/Al laminate with good bonding quality and mechanical properties was s...Fabricating Mg/Al laminate is an effective strategy to circumvent the inherently low formability and poor corrosion resistance of Mg alloys.Here,Mg/Al laminate with good bonding quality and mechanical properties was successfully fabricated via porthole die co-extrusion process using ZK60 Mg and TiB_(2)/6061Al composite as constituted layers.Integrating the results from microstructural characterization and mechanical testing,the effects of extrusion temperature on microstructure,interfacial structure,element diffusion,and mechanical properties were investigated.The results show that Mg/Al laminate achieves a sound welding quality by mechanical bonding and diffusion bonding.The obvious intermetallic compounds(βandγ)layer forms at Mg/Al interface,and its thickness increases to 8.3μm as the extrusion temperature reaches 400℃.High extrusion temperature promotes the dynamic recrystallization and grain growth of Mg and Al layers,while the dislocation density decreases.β/γinterface shows a coherent feature,whileγ/Mg interface is semi-coherent with a locally ordered transition zone of 4.5 nm.The rich Mg and Cr layers are found at TiB_(2)/6061 interface,which is conducive to improving the bonding quality.When the extrusion temperature is 370℃,the thickness of diffusion layer is around 5.0μm,and the bonding strength reaches 18.68 MPa,resulting in the best comprehensive mechanical properties.This work provides a new direction for the development of Mg/Al laminate with excellent strength and ductility.展开更多
The microstructural characterization,corrosion behavior and tensile properties of the extruded lean Mg−1Bi−0.5Sn−0.5In(wt.%)alloy were investigated through scanning electron microscopy(SEM),electron backscatter diffra...The microstructural characterization,corrosion behavior and tensile properties of the extruded lean Mg−1Bi−0.5Sn−0.5In(wt.%)alloy were investigated through scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),X-ray photoelectron spectroscopy(XPS),electrochemical measurements and tensile tests.The results reveal that a microstructure consisting of dynamically recrystallized and deformed grains is obtained.Notably,the investigated alloy exhibits excellent strength−ductility synergy,with tensile yield strength(TYS),ultimate tensile strength(UTS)and elongation(EL)of 254.8 MPa,315.4 MPa,and 25.3%,respectively.Furthermore,in 3.5 wt.%NaCl solution,with the increase of immersion time,the dominant corrosion mechanism of the studied alloy transforms from pitting corrosion to filiform corrosion.After the immersion for 24 h,a composite oxide film(SnO2−Bi2O3−In2O3)is formed,which delays the corrosion process,and the corrosion rate(PH=1.53 mm/a)is finally stabilized.展开更多
The high-strength Mg-7Sn alloys(wt.%)with a heterogeneous grain structure were prepared by low-temperature extrusion(230°C)with the extrusion ratio of 9:1(9E230)and 17:1(17E230).The two extruded alloys contained ...The high-strength Mg-7Sn alloys(wt.%)with a heterogeneous grain structure were prepared by low-temperature extrusion(230°C)with the extrusion ratio of 9:1(9E230)and 17:1(17E230).The two extruded alloys contained fine dynamic recrystallization(DRX)grains(FG)and coarse un DRX grains(CG).The difference in deformability between CG and FG leads to the formation of heterogeneous grain structure.The average grain size and basal texture intensities increased while the volume fraction of CG decreased with increasing extrusion ratio.Tensile testing results indicated that the extruded 17E230 alloy exhibited higher tensile strengths than 9E230 alloy,whose tensile yield strength(σ_(0.2)),ultimate tensile strengths(σ_(b)),and elongation to failure(ε_(f))were 231.1 MPa,319.5MPa,and 12.54%respectively.The high tensile strengths of the extruded alloy mainly originated from grain refinement,texture strengthening,precipitation strengthening from a great number of nano-scale Mg_(2)Sn phases,solid solution strengthening and hetero-deformation induced(HDI)strengthening,while the good ductility of the alloy was also mainly attributed to grain refinement,activation of the non-basal slip systems and HDI hardening.展开更多
To tackle the common issue of green defects in material extrusion(MEX)additive manufacturing(AM)cemented carbides,warm isostatic pressing(WIP)was introduced to eliminate defects of MEX WC-9Co cemented carbide greens,t...To tackle the common issue of green defects in material extrusion(MEX)additive manufacturing(AM)cemented carbides,warm isostatic pressing(WIP)was introduced to eliminate defects of MEX WC-9Co cemented carbide greens,thereby improving both microstructure uniformity and mechanical properties of sintered bodies.The results indicate that WIP reduces defects in MEX greens,thus decreasing the dimensions and numbers of defects,modifying shapes of pores within sintered bodies,while preserving surface quality and shape characteristics.Compared with WC-9Co prepared via MEX followed by debinding and sintering(DS),the hardness of WC-9Co prepared using MEX-WIP-DS does not change significantly,ranging HV_(30)1494-1508,the transverse rupture strength increases by up to 49.3%,reaching 2998-3514 MPa,and the fracture toughness remains high,ranging 14.8-17.0 MPa·m^(1/2).The mechanical properties surpass comparable cemented carbides fabricated through other AM methods and are comparable to those produced by powder metallurgy.The integration of green WIP into MEX-DS broadens the MEX processing window,and improves the overall mechanical properties of MEX AM WC-Co cemented carbides.展开更多
Based on thermodynamic calculations and continuous rheological extrusion(CRE)technology,Al-Ti-V-B master alloys were designed and prepared.The morphology and the distribution of the refined phases in the master alloys...Based on thermodynamic calculations and continuous rheological extrusion(CRE)technology,Al-Ti-V-B master alloys were designed and prepared.The morphology and the distribution of the refined phases in the master alloys were analyzed by XRD,SEM,and TEM.The effects of master alloy addition and holding time on the microstructure and mechanical properties of A356 alloy were investigated.Under the optimum refiner addition of 0.3wt.%and the holding time of 20 min,the average grain size of the refined A356 alloy is 151.8±9.11μm,89.62%lower than that of original A356 alloy.The tensile strength and elongation of as-cast A356refined alloy are 196.11 MPa and 5.75%,respectively.After T6 treatment,the tensile strength and elongation of A356 refined alloy are 290.1 MPa and 3.09%,respectively.The fracture morphology is characterized by a predominance of along-crystal fracture with a small amount of through-crystal fracture,attributed to the refined grains.Finer grains promote crack path deflection and localized plastic deformation,enhancing energy dissipation and reducing the tendency for brittle fracture.This study provides a novel approach to improving the mechanical properties of A356 alloy through grain refinement using CRE Al-Ti-V-B master alloy.展开更多
The Mg−Al composite rods of aluminum core-reinforced magnesium alloy were prepared by the extrusion−shear(ES)process,and the microstructure,deformation mechanism,and mechanical properties of the Mg−Al composite rods w...The Mg−Al composite rods of aluminum core-reinforced magnesium alloy were prepared by the extrusion−shear(ES)process,and the microstructure,deformation mechanism,and mechanical properties of the Mg−Al composite rods were investigated at different extrusion temperatures and shear stresses.The experimental results show that the proportion of dynamic recrystallization(DRX)and texture for Al and Mg alloys are controlled by the combination of temperature and shear stress.The texture type of the Al alloys exhibits slight variations at different temperatures.With the increase of temperature,the DRX behavior of Mg alloy shifts from discontinuous DRX(DDRX),continuous DRX(CDRX),and twin-induced DRX(TDRX)dominant to CDRX,the dislocation density in Mg alloy grains decreases significantly,and the average value of Schmid factor(SF)of the basalslip system increases.In particular,partial grains exhibit a distinct dominant slip system at 390℃.The hardness and thickness of the bonding layer,as well as the yield strength and elongation of the Mg alloy,reach their maximum at 360℃as a result of the intricate influence of the combined temperature and shear stress.展开更多
A new triple melting method with hot extrusion process for GH4710 alloy ingots has been developed to overcome the difficulty in deformation of GH4710 alloy prepared by the casting and forging process.The as-extruded G...A new triple melting method with hot extrusion process for GH4710 alloy ingots has been developed to overcome the difficulty in deformation of GH4710 alloy prepared by the casting and forging process.The as-extruded GH4710 alloy was analyzed through the isothermal compression experiment and metallographic analysis.The viscoelastic stress characteristics and dynamic recrystallization(DRX)behavior of the as-extruded GH4710 alloy were investigated during deformation at temperatures ranging from 1050℃ to 1120℃ and strain rates ranging from 0.01 s^(−1) to 5.00 s^(−1).The true stress-true strain curves,average grain size,and DRX volume fraction were also obtained under various deformation conditions.Prediction models for DRX volume fraction and grain size of the as-extruded GH4710 alloy were established using the statistical regression method.The model was implanted into the Derform-3D software,and numerical simulation of the microstructure evolution of GH4710 alloy was conducted.Firstly,the isothermal compression simulations were conducted using the finite element method to verify the accuracy of prediction model.Subsequently,the prediction model was applied to perform an optimization analysis of the forging process for a turbine disk with a diameter of 300 mm.Results show a strong correlation between the simulated results and the actual microstructure of the turbine disk forged through the optimal process parameters.The optimal process parameters are deformation temperature of 1100℃ and forging speed of 0.2 mm/s.This established DRX prediction model can serve as a fundamental reference for understanding the microstructural evolution during the hot deformation process of as-extruded GH4710 alloy.展开更多
Fibre Extrusion Technology Ltd(FET)of Leeds,UK designs,develops and manufactures extrusion equipment for a wide range of high value textile material applications worldwide.The company has built strong business relatio...Fibre Extrusion Technology Ltd(FET)of Leeds,UK designs,develops and manufactures extrusion equipment for a wide range of high value textile material applications worldwide.The company has built strong business relationships across global markets,including a growing presence in Southeast Asia where technical textile development is advancing rapidly.FET boasts a number of specialist technical agents throughout Asia and is seeking to further expand its customer service in the future.展开更多
The Mg-Y-Zn magnesium alloy system is known for the presence of Long-Period Stacking Ordered(LPSO)phases that improves strength and ductility with minimal amounts of alloying elements.Even better improvements are asso...The Mg-Y-Zn magnesium alloy system is known for the presence of Long-Period Stacking Ordered(LPSO)phases that improves strength and ductility with minimal amounts of alloying elements.Even better improvements are associated with the specific microstructure known as the Mille-Feuille(MF)structure that can occur in this alloy as well after proper heat treatment.This study systematically compares the traditional ingot metallurgy method with the Bridgman method(slow cooling),coupled with diverse heat treatments and extrusion process.Microscopic analyses reveal variations in the presence of LPSO phases,MF structure,and especially grain size,leading to divergent mechanical and corrosion properties.The Bridgman approach surprisingly stands out,ensuring superior mechanical properties due to kink and texture strengthening.展开更多
Prefabricated twinning represents an effective strategy for optimizing the microstructure of extruded forming components and facilitating changes in texture.The study examines the incorporation of[10-12]twins into an ...Prefabricated twinning represents an effective strategy for optimizing the microstructure of extruded forming components and facilitating changes in texture.The study examines the incorporation of[10-12]twins into an AZ31 magnesium alloy billet via cold pre-upsetting deformation before alternating forward extrusion(CUAFE).The experimental results indicate that the initial presence of[10-12]twins is advantageous for the development of[10-10]and[11-20]texture components during the extrusion process.In addition,different DRX mechanisms have different influences on the evolution of basal texture.The CDRX grains tend to preferentially select the[11-20]texture orientation,weakening the[10-10]texture and enhancing the[11-20]texture.However,most DDRX grains deviate significantly from the orientation of their surrounding original grain and do not have a preferred orientation.This is reflected in the mechanical properties of the CUAFE part.The tensile strength is 323.5 MPa,while the elongation is as high as 20.1%.展开更多
基金supported by the National Natural Sciences Foundation of China(No. 40472057)the National Major Basic Development Project(2006CB403503)
文摘Most of the so-called Bayan Obo fine-grained dolomite marbles collected from the main and east orebodies show a microporphyritic texture,namely the microphenocrysts are set in a very finegrained matrix,although nearly all of them have undergone recrystallization caused either by deformation or alteration.The texture seems likely to have maintained the original features.It is known that one of the most characteristic textures of volcanic rocks is the porphyritic texture,and the microporphyritic texture is a variety in which both the phenocrysts and the matrix are only distinguishable with the microscope.Therefore,the dolomite marbles in the main and east orebodies may be related to the extrusive carbonatites.In addition,there also occur some carbonatite sills and dykes with different textures at Bayan Obo.Thus,the Bayan Obo carbonatites are polyphase intrusive and extrusive carbonatites.
基金supported by the National Key Research and Development Program of China(Grant No.2023YFB3710805).
文摘Ultra-high-strength aluminumalloy profile is an ideal choice for aerospace structuralmaterials due to its excellent specific strength and corrosion resistance.However,issues such as uneven metal flow,stress concentration,and forming defects are prone to occur during their extrusion.This study focuses on an Al-Zn-Mg-Cu ultra-high-strength aluminum alloy profile with a double-U,multi-cavity thin-walled structure.Firstly,hot compression experiments were conducted at temperatures of 350○C,400○C,and 450○C,with strain rates of 0.01 and 1.0 s^(−1),to investigate the plastic deformation behavior of the material.Subsequently,a 3D coupled thermo-mechanical extrusion simulation model was established using Deform-3D to systematically analyze the influence of die structure and process parameters on metal flow velocity,effective stress/strain,and temperature distribution.The simulation revealed significant velocity differences,stress concentration,and uneven temperature distribution.Key parameters,including mesh density,extrusion ratio,die fillet,and bearing length,were optimized through full-factorial experiments.This optimization,combined with a stepped flow-guiding die design,effectively improved the metal flow pattern during extrusion.Trial production based on both the initial and optimized parameters were carried out.A comparative analysis demonstrates that the optimized scheme results in a final profile whose cross-section matches the target design closely,with complete filling of complex features and no obvious forming defects.This research provides a valuable reference for the extrusion process optimization and die design of complex-section profiles made from ultra-high-strength aluminum alloys.
文摘Fibre Extrusion Technology Ltd(FET)of Leeds,UK reported another successful exhibition at COMPAMED 2025 in Dusseldorf,following closely on the heels of ITMA ASIA in Singapore.This was the second time that FET had exhibited at this leading international trade fair for the medical technology supplier sector,a reflection of the company’s growing role in this sector.More than half of FET’s turnover is currently derived from the burgeoning medical market.COMPAMED is aimed at suppliers of a wide range of high-quality medical technology components,services and production equipment for the medical industry.FET’s expanding role in the medical sector is therefore an ideal fit for this trade show.
基金support of the Korea Institute of Industrial Technol-ogy as“Development of a remote manufacturing system for high-risk,high-difficulty pipe production processes”(kitech EH-25-0004)supported by the Technology Innovation Program(or Industrial Strategic Technology Development Program)(RS-2023–00237714+2 种基金Development of Dynamic Metrology Tool for CMP Process StabilizationRS-2025–02634755Development of Real-Time Electrical Fire Prevention System Technology Reflecting the Characteristics of Traditional Markets)funded by the Ministry of Trade,Industry&Energy(MOTIE,Republic of Korea).
文摘The composite material layering process has attracted considerable attention due to its production advantages,including high scalability and compatibility with a wide range of raw materials.However,changes in process conditions can lead to degradation in layer quality and non-uniformity,highlighting the need for real-time monitoring to improve overall quality and efficiency.In this study,an AI-based monitoring system was developed to evaluate layer width and assess quality in real time.Three deep learning models Faster Region-based Convolutional Neural Network(R-CNN),You Only Look Once version 8(YOLOv8),and Single Shot MultiBox Detector(SSD)were compared,and YOLOv8 was ultimately selected for its superior speed,flexibility,and scalability.The selected model was integrated into a user-friendly interface.To verify the reliability of the system,bead width control experiments were conducted,which identified feed speed and extrusion speed as the key process parameters.Accordingly,a Central Composite Design(CCD)experimental plan with 13 conditions was applied to evaluate layer width and validate the system’s reliability.Finally,the proposed system was applied to the additive manufacturing of an aerospace component,where it successfully detected bead width deviations during printing and enabled stable fabrication with a maximum geometric deviation of approximately 6 mm.These findings demonstrate the critical role of real-time monitoring of layer width and quality in improving process stability and final product quality in composite material additive manufacturing.
基金supported by the National Key Research and Development Program of China (2023YFF1103404)the Key Research & Development Program of Shaanxi Province (2022NY-010)。
文摘In this study,we investigated the effect of high-solubility wheat gluten proteins(hs-WGP) prepared by pH-cycle treatment on soybean isolate-based extrudates.The results showed that the addition of hs-WGP can improve textural properties of soybean isolate-based extrudate via regulating the hardness to appropriate range.At molecular level,it was further found that the hs-WGP was cross-linked with soy protein isolate mainly through hydrogen bonding and disulfide bonding,and the spherical protein of soy protein isolate was wrapped by the hs-WGP,which weakened the thermal unfolding of globular proteins during heating process,reduced the degree of heat-curing gel,resulted in a reduction in hardness.In addition,hs-WGP/soybean protein composite extrudates possessed a more balanced amino acid composition,which have a positive impact on meat analogues at the nutritional level.
基金supported by the National Science and Technology Major Project,China(No.2019-VI-0004-0118)the National Natural Science Foundation of China(No.51771152)the National Key R&D Program of China(No.2018YFB1106800)。
文摘Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed slightly.The dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)increased.With the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical<2111>-<1123>rare-earth(RE)textures.The alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening contributions.These results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.
基金Natural Science Foundation of Shandong Province of China(ZR2023QE193)。
文摘The microstructures and mechanical properties of Al-8.3Zn-3.3Cu-2.2Mg alloys prepared via hot extrusion and liquid forging methods were investigated.Results show that based on DEFORM simulation analysis,the optimal hot extrusion parameters are determined as ingot initial temperature of 380°C and extrusion speed of 3 mm/s.The hot-extruded aluminum alloy after T6 heat treatment presents superior mechanical properties with yield strength of 519.6 MPa,ultimate tensile strength of 582.1 MPa,and elongation of 11.0%.Compared with the properties of gravity-cast and liquid-forged alloys,the yield strength of hot-extruded alloy increases by 30.8%and 4.9%,and the ultimate tensile strength improves by 43.5%and 10.2%,respectively.The significant improvement in tensile strength of the hot-extruded alloys is attributed to the elimination of casting defects and the refinement of matrix grain and eutectic phases.In addition,the hot-extruded alloy demonstrates superior plasticity compared with the liquid-forged alloy.This is because severe plastic deformation occurs during hot extrusion,which effectively breaks and disperses the eutectic phases,facilitating the dissolution and precipitation of the second phases and inhibiting the microcrack initiation.
基金supported by the National Research Foundation of Korea(NRF)grants funded by the Korea government(MSIT)(Nos.RS-2024–00351052 and RS-2024–00450561).
文摘This study compares the microstructural evolution,dynamic recrystallization(DRX)behavior,tensile properties,and age-hardenability between the newly developed high-speed-extrudable BA56 alloy and those of the widely recognized AZ31 alloy in industry.Unlike the AZ31 alloy,which retains partially unrecrystallized grains,the high-speed-extruded BA56 alloy demonstrates a coarser but entirely recrystallized and more homogeneous microstructure.The fine-grained structure and abundant Mg_(3)Bi_(2) particles in the BA56 extrusion billet significantly enhance its DRX behavior,thus enabling rapid and complete recrystallization during extrusion.The BA56 alloy contains band-like fragmented Mg_(3)Bi_(2) particles and numerous fine Mg_(3)Bi_(2) particles distributed throughout the material,in contrast to the sparse Al_(8)Mn_(5) particles in the AZ31 alloy.These features contribute to superior mechanical properties of the BA56 alloy,which achieves tensile yield and ultimate tensile strengths of 205 and 292 MPa,respectively,compared to 196 and 270 MPa for the AZ31 alloy.The superior strength of the BA56 alloy,even with its coarser grain size,can be explained by its elevated Hall-Petch constant and the strengthening contribution from the fine Mg_(3)Bi_(2) particles.Additionally,the BA56 alloy demonstrates significant age-hardenability,achieving a 22%enhancement in hardness following T5 aging,attributed to the precipitation of nanoscale Mg_(3)Bi_(2) and Mg_(17)Al_(12) phases.By contrast,the AZ31 alloy shows minimal hardening due to the absence of precipitate formation during aging.These findings suggest that the BA56 alloy is a promising candidate for the production of extruded Mg components requiring a combination of high productivity,superior mechanical performance,and wide-ranging process adaptability.
基金supports from the National Natural Science Foundation of China(52175338 and 52222510)Science Fund for Distinguished Young Scholars of Shandong Province(ZR2021JQ21)Key Research and Development Program of Shandong Province(2021ZLGX01).
文摘Fabricating Mg/Al laminate is an effective strategy to circumvent the inherently low formability and poor corrosion resistance of Mg alloys.Here,Mg/Al laminate with good bonding quality and mechanical properties was successfully fabricated via porthole die co-extrusion process using ZK60 Mg and TiB_(2)/6061Al composite as constituted layers.Integrating the results from microstructural characterization and mechanical testing,the effects of extrusion temperature on microstructure,interfacial structure,element diffusion,and mechanical properties were investigated.The results show that Mg/Al laminate achieves a sound welding quality by mechanical bonding and diffusion bonding.The obvious intermetallic compounds(βandγ)layer forms at Mg/Al interface,and its thickness increases to 8.3μm as the extrusion temperature reaches 400℃.High extrusion temperature promotes the dynamic recrystallization and grain growth of Mg and Al layers,while the dislocation density decreases.β/γinterface shows a coherent feature,whileγ/Mg interface is semi-coherent with a locally ordered transition zone of 4.5 nm.The rich Mg and Cr layers are found at TiB_(2)/6061 interface,which is conducive to improving the bonding quality.When the extrusion temperature is 370℃,the thickness of diffusion layer is around 5.0μm,and the bonding strength reaches 18.68 MPa,resulting in the best comprehensive mechanical properties.This work provides a new direction for the development of Mg/Al laminate with excellent strength and ductility.
基金supported by the National Natural Science Foundation of China(No.51901153)the Natural Science Foundation of Shanxi,China(No.202103021224049)+1 种基金the Shanxi Zhejiang University New Materials and Chemical Research Institute Scientific Research Project,China(No.2022SX-TD025)the Open Project of Salt Lake Chemical Engineering Research Complex,Qinghai University,China(No.2023-DXSSKF-Z02).
文摘The microstructural characterization,corrosion behavior and tensile properties of the extruded lean Mg−1Bi−0.5Sn−0.5In(wt.%)alloy were investigated through scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),X-ray photoelectron spectroscopy(XPS),electrochemical measurements and tensile tests.The results reveal that a microstructure consisting of dynamically recrystallized and deformed grains is obtained.Notably,the investigated alloy exhibits excellent strength−ductility synergy,with tensile yield strength(TYS),ultimate tensile strength(UTS)and elongation(EL)of 254.8 MPa,315.4 MPa,and 25.3%,respectively.Furthermore,in 3.5 wt.%NaCl solution,with the increase of immersion time,the dominant corrosion mechanism of the studied alloy transforms from pitting corrosion to filiform corrosion.After the immersion for 24 h,a composite oxide film(SnO2−Bi2O3−In2O3)is formed,which delays the corrosion process,and the corrosion rate(PH=1.53 mm/a)is finally stabilized.
基金supported by the Major Science and Technology Project of Gansu Province(Grant No.22ZD6GA008)the National Natural Science Foundation of China(Nos.52261027,52001152 and 51961021)+2 种基金the Open Project of State Key Laboratory for Mechanical Behavior of Materials(20192102)Undergraduate Innovation and Entrepreneurship Training Program(Nos.DC20231482,DC20231188 and DC20231558)Gansu Provincial Excellent Graduate Students“Innovation Star”Program(2022CXZX-394)。
文摘The high-strength Mg-7Sn alloys(wt.%)with a heterogeneous grain structure were prepared by low-temperature extrusion(230°C)with the extrusion ratio of 9:1(9E230)and 17:1(17E230).The two extruded alloys contained fine dynamic recrystallization(DRX)grains(FG)and coarse un DRX grains(CG).The difference in deformability between CG and FG leads to the formation of heterogeneous grain structure.The average grain size and basal texture intensities increased while the volume fraction of CG decreased with increasing extrusion ratio.Tensile testing results indicated that the extruded 17E230 alloy exhibited higher tensile strengths than 9E230 alloy,whose tensile yield strength(σ_(0.2)),ultimate tensile strengths(σ_(b)),and elongation to failure(ε_(f))were 231.1 MPa,319.5MPa,and 12.54%respectively.The high tensile strengths of the extruded alloy mainly originated from grain refinement,texture strengthening,precipitation strengthening from a great number of nano-scale Mg_(2)Sn phases,solid solution strengthening and hetero-deformation induced(HDI)strengthening,while the good ductility of the alloy was also mainly attributed to grain refinement,activation of the non-basal slip systems and HDI hardening.
基金supported by the Key Project of Chinese Academy of Engineering(No.2019-XZ-11)the General Project of Chinese Academy of Engineering(No.2023-XY-18)+1 种基金the Open Fund of National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials of China(No.HKDNM201907)the Independent Project of State Key Laboratory of Powder Metallurgy,China。
文摘To tackle the common issue of green defects in material extrusion(MEX)additive manufacturing(AM)cemented carbides,warm isostatic pressing(WIP)was introduced to eliminate defects of MEX WC-9Co cemented carbide greens,thereby improving both microstructure uniformity and mechanical properties of sintered bodies.The results indicate that WIP reduces defects in MEX greens,thus decreasing the dimensions and numbers of defects,modifying shapes of pores within sintered bodies,while preserving surface quality and shape characteristics.Compared with WC-9Co prepared via MEX followed by debinding and sintering(DS),the hardness of WC-9Co prepared using MEX-WIP-DS does not change significantly,ranging HV_(30)1494-1508,the transverse rupture strength increases by up to 49.3%,reaching 2998-3514 MPa,and the fracture toughness remains high,ranging 14.8-17.0 MPa·m^(1/2).The mechanical properties surpass comparable cemented carbides fabricated through other AM methods and are comparable to those produced by powder metallurgy.The integration of green WIP into MEX-DS broadens the MEX processing window,and improves the overall mechanical properties of MEX AM WC-Co cemented carbides.
基金supported by the National Key Research and Development Program of China (Grant No.2022YFB3706801)the National Natural Science Foundation of China (Grant Nos.U2341253,52371019,U2241232)+2 种基金the Dalian High-level Talents Innovation Support Program (Grant No.2021RD06)the Applied Basic Research Program of Liaoning Province (Grant No.2022JH2/101300003)the Natural Science Foundation of Liaoning Province (Grant Nos.2022-BS-262,JYTMS20230031)。
文摘Based on thermodynamic calculations and continuous rheological extrusion(CRE)technology,Al-Ti-V-B master alloys were designed and prepared.The morphology and the distribution of the refined phases in the master alloys were analyzed by XRD,SEM,and TEM.The effects of master alloy addition and holding time on the microstructure and mechanical properties of A356 alloy were investigated.Under the optimum refiner addition of 0.3wt.%and the holding time of 20 min,the average grain size of the refined A356 alloy is 151.8±9.11μm,89.62%lower than that of original A356 alloy.The tensile strength and elongation of as-cast A356refined alloy are 196.11 MPa and 5.75%,respectively.After T6 treatment,the tensile strength and elongation of A356 refined alloy are 290.1 MPa and 3.09%,respectively.The fracture morphology is characterized by a predominance of along-crystal fracture with a small amount of through-crystal fracture,attributed to the refined grains.Finer grains promote crack path deflection and localized plastic deformation,enhancing energy dissipation and reducing the tendency for brittle fracture.This study provides a novel approach to improving the mechanical properties of A356 alloy through grain refinement using CRE Al-Ti-V-B master alloy.
基金supported by the general project of the National Natural Science Foundation of China(No.52071042)Chongqing Natural Science Foundation Project,China(Nos.CSTB2023NSCQ-MSX0079,cstc2021ycjh-bgzxm0148)Graduate Student Innovation Program of Chongqing University of Technology,China(No.gzlcx20232008).
文摘The Mg−Al composite rods of aluminum core-reinforced magnesium alloy were prepared by the extrusion−shear(ES)process,and the microstructure,deformation mechanism,and mechanical properties of the Mg−Al composite rods were investigated at different extrusion temperatures and shear stresses.The experimental results show that the proportion of dynamic recrystallization(DRX)and texture for Al and Mg alloys are controlled by the combination of temperature and shear stress.The texture type of the Al alloys exhibits slight variations at different temperatures.With the increase of temperature,the DRX behavior of Mg alloy shifts from discontinuous DRX(DDRX),continuous DRX(CDRX),and twin-induced DRX(TDRX)dominant to CDRX,the dislocation density in Mg alloy grains decreases significantly,and the average value of Schmid factor(SF)of the basalslip system increases.In particular,partial grains exhibit a distinct dominant slip system at 390℃.The hardness and thickness of the bonding layer,as well as the yield strength and elongation of the Mg alloy,reach their maximum at 360℃as a result of the intricate influence of the combined temperature and shear stress.
基金Key Field Research Foundation of Beijing Institute of Aeronautical Materials(KJSC192309)。
文摘A new triple melting method with hot extrusion process for GH4710 alloy ingots has been developed to overcome the difficulty in deformation of GH4710 alloy prepared by the casting and forging process.The as-extruded GH4710 alloy was analyzed through the isothermal compression experiment and metallographic analysis.The viscoelastic stress characteristics and dynamic recrystallization(DRX)behavior of the as-extruded GH4710 alloy were investigated during deformation at temperatures ranging from 1050℃ to 1120℃ and strain rates ranging from 0.01 s^(−1) to 5.00 s^(−1).The true stress-true strain curves,average grain size,and DRX volume fraction were also obtained under various deformation conditions.Prediction models for DRX volume fraction and grain size of the as-extruded GH4710 alloy were established using the statistical regression method.The model was implanted into the Derform-3D software,and numerical simulation of the microstructure evolution of GH4710 alloy was conducted.Firstly,the isothermal compression simulations were conducted using the finite element method to verify the accuracy of prediction model.Subsequently,the prediction model was applied to perform an optimization analysis of the forging process for a turbine disk with a diameter of 300 mm.Results show a strong correlation between the simulated results and the actual microstructure of the turbine disk forged through the optimal process parameters.The optimal process parameters are deformation temperature of 1100℃ and forging speed of 0.2 mm/s.This established DRX prediction model can serve as a fundamental reference for understanding the microstructural evolution during the hot deformation process of as-extruded GH4710 alloy.
文摘Fibre Extrusion Technology Ltd(FET)of Leeds,UK designs,develops and manufactures extrusion equipment for a wide range of high value textile material applications worldwide.The company has built strong business relationships across global markets,including a growing presence in Southeast Asia where technical textile development is advancing rapidly.FET boasts a number of specialist technical agents throughout Asia and is seeking to further expand its customer service in the future.
基金supported by Japan Society for the Promotion of Science(KAKENHI Grant-in-Aid for Scientific Research,18H05475,18H05476 and JP20H00312)MRC International Collaborative Research Grant+4 种基金The authors would like to thank the Czech Science Foundation(Project No.22-22248S)specific university research(A1_FCHT_2024_007)for financial supportsupported by the Ministry of Education,Youth,and Sports of the Czech Republic.Project No.CZ.02.01.01/00/22_008/0004591co-funded by the European UnionCzechNanoLab project LM2023051 funded by MEYS CR is gratefully acknowledged for the financial support of the measurements/sample fabrication at LNSM Research Infrastructure。
文摘The Mg-Y-Zn magnesium alloy system is known for the presence of Long-Period Stacking Ordered(LPSO)phases that improves strength and ductility with minimal amounts of alloying elements.Even better improvements are associated with the specific microstructure known as the Mille-Feuille(MF)structure that can occur in this alloy as well after proper heat treatment.This study systematically compares the traditional ingot metallurgy method with the Bridgman method(slow cooling),coupled with diverse heat treatments and extrusion process.Microscopic analyses reveal variations in the presence of LPSO phases,MF structure,and especially grain size,leading to divergent mechanical and corrosion properties.The Bridgman approach surprisingly stands out,ensuring superior mechanical properties due to kink and texture strengthening.
基金supported by the National Natural Science Foundation of China(No.52475341).
文摘Prefabricated twinning represents an effective strategy for optimizing the microstructure of extruded forming components and facilitating changes in texture.The study examines the incorporation of[10-12]twins into an AZ31 magnesium alloy billet via cold pre-upsetting deformation before alternating forward extrusion(CUAFE).The experimental results indicate that the initial presence of[10-12]twins is advantageous for the development of[10-10]and[11-20]texture components during the extrusion process.In addition,different DRX mechanisms have different influences on the evolution of basal texture.The CDRX grains tend to preferentially select the[11-20]texture orientation,weakening the[10-10]texture and enhancing the[11-20]texture.However,most DDRX grains deviate significantly from the orientation of their surrounding original grain and do not have a preferred orientation.This is reflected in the mechanical properties of the CUAFE part.The tensile strength is 323.5 MPa,while the elongation is as high as 20.1%.
