This paper endeavors to explore the integration of curriculum ideological and political elements into the blended teaching of the Design Composition course based on the OBE(outcome-based education)concept.It analyzes ...This paper endeavors to explore the integration of curriculum ideological and political elements into the blended teaching of the Design Composition course based on the OBE(outcome-based education)concept.It analyzes the implementation paths and practical effects,providing a reference for the integration of ideological and political education and professional education in art design education in the new era.By analyzing the core content of the OBE concept in combination with the characteristics of the Design Composition course,we discuss the integration of ideological and political elements into teaching design.Employing methods of case analysis and literature review,and in conjunction with the blended teaching mode,we design a teaching process that conforms to the OBE concept,optimize practical activities and evaluation systems,and enhance students’ideological and moral qualities as well as disciplinary accomplishments.The research reveals that through the integration of ideological and political education in courses based on the OBE concept,it is possible to not only improve students’professional skills but also enhance their sense of social responsibility and cultural confidence.展开更多
Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler ...Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects.展开更多
Gold-platinum(Au-Pt)alloy has aroused considerable attention due to its ultra-low magnetic susceptibility(MS)in testing mass(TM)on spacecraft.However,the effect of Au content on the properties of the alloy has not yet...Gold-platinum(Au-Pt)alloy has aroused considerable attention due to its ultra-low magnetic susceptibility(MS)in testing mass(TM)on spacecraft.However,the effect of Au content on the properties of the alloy has not yet been understood.In this study,the composition design of Au-Pt alloy with ultra-low MS was achieved through density functional theory(DFT)and experimental methods.The elastic,thermal properties and electronic structure were systematically investigated,the composition range was further optimized and Au75Pt25 was determined to be the most suitable alloy for TM material.The phase composition of this alloy after cold rolling and solid solution was characterized,indicating a single-phase FCC structure.In addition,there is a good validation between the experimental Vickers hardness and the DFT results.This work provides new insights into the compositional optimization of Au-Pt alloys and lays the foundation for alloy development.展开更多
The solidification paths of Al-Zn-Mg-Cu alloys and its precipitation behavior are analyzed using software package JMatPro 6.0 for material property simulation of Al-base alloys.The microstructures of the experimental ...The solidification paths of Al-Zn-Mg-Cu alloys and its precipitation behavior are analyzed using software package JMatPro 6.0 for material property simulation of Al-base alloys.The microstructures of the experimental alloys are analyzed;the experimental results of microstructural analysis are in agreement with the thermodynamic prediction.Through orthogonal experimental method,this paper designs the composition of Al-Zn-Mg-Cu alloys by studying the variation of η(MgZn2) phase,S(Al2CuMg) phase,T(AlZnMgCu) phase amount and precipitation temperatures with different Zn,Mg and Cu contents.It is found that with the optimum mass fraction of Zn of 6.7%,Mg of 2.2%-2.5% and Cu of 1.6%-2.0%,the mass fraction of η phase can be up to 8.7%-9.22% and that of S phase and T phase can be lower than 0.5%.展开更多
The improvement of machining behavior of prehardened-mould steel for plastic is realized by using computer-aided composition design in this work. The results showed that the matrix composition of large sectional preha...The improvement of machining behavior of prehardened-mould steel for plastic is realized by using computer-aided composition design in this work. The results showed that the matrix composition of large sectional prehardened mould steel for plastic markedly influences the precipitation of non-metallic inclusion and the control of composition aided by Thermo-Calc software package minimizes the amount of detrimental oxide inclusion. In addition the modification of calcium is optimized in the light of composition design.展开更多
Theempiricalelectrontheory of solidsand molecules( EET) and theimproved TFDtheory wereapplied tocalculatethe phasestructurefactorsand interfaceconjunction factorsofcom mon alloying elementsincastiron. Akind of Si- M...Theempiricalelectrontheory of solidsand molecules( EET) and theimproved TFDtheory wereapplied tocalculatethe phasestructurefactorsand interfaceconjunction factorsofcom mon alloying elementsincastiron. Akind of Si- Mo- Cu ductileiron with rareearth Mg asnodularizer was designed accordingtothese valenceelectron structure parameters. Actual applicationtestsshow thatthelongevity of thisiron is 1.5 timesof thatof high manganesesteel. This accordance of theoretical results and actual effectsshows the composition design methodcan beused in othercastiron research.展开更多
For austenitic octahedral segregation structure units, their pure mathematics statistic distribu!ive probability is calculated by the empirical electron theory （EET） of solids and molecules and K-B formula. The prac...For austenitic octahedral segregation structure units, their pure mathematics statistic distribu!ive probability is calculated by the empirical electron theory （EET） of solids and molecules and K-B formula. The practical distributive probability can be obtained only if the statistic distribution of austenitic octahedral segregation structure units and the interaction of the alloying elements in steel are considered. Based on 8 groups of experimental data of original steels, three empirical formulas revealing relationships between material macromechanics factor （Sm） and tensile strength （ab）, or impact energy （AK）, or hardness （HRC） of multi-component medium-low-alloy steels were established, respectively. Through the three empirical formulas, new supersaturated carburizing steel has been successfully designed and developed. The other 2 groups of the original experimental steels are used as the standard steel for testing the percentage error of the new steel. The results show that the calculated values are well consistent with those of measured ones and the new supersaturated carburized steel can meet the requirements of the die assembly of cold-drawn seamless stainless steel tube of Taiyuan Iron ＆ Steel （Group） Company LTD.展开更多
Erratum to:International Journal of Minerals, Metallurgy and Materials Volume 26, Number 9, September 2019, Page 1151https://doi.org/10.1007/s12613-019-1854-1The original version of this article unfortunately containe...Erratum to:International Journal of Minerals, Metallurgy and Materials Volume 26, Number 9, September 2019, Page 1151https://doi.org/10.1007/s12613-019-1854-1The original version of this article unfortunately contained a mistake. The presentation of Fig. 11 was incorrect. The correct version is given below:展开更多
The composition of a bearing steel was designed for limited hardenability by use of Grossmann's method. A medium frequency induction Process was applied to heat bearings to ensure penetrant heating and suitable so...The composition of a bearing steel was designed for limited hardenability by use of Grossmann's method. A medium frequency induction Process was applied to heat bearings to ensure penetrant heating and suitable solving of carbon and other elements in the matrix. The hardened depth measured from the end quenching test samples and actual bearings matches well with the designed one.展开更多
Multi-principal element alloys(MPEAs)have shown extraordinary properties in different fields.However,the composition design of MPEAs is still challenging due to the complicated interactions among principal elements(PE...Multi-principal element alloys(MPEAs)have shown extraordinary properties in different fields.However,the composition design of MPEAs is still challenging due to the complicated interactions among principal elements(PEs),and even more challenging with precipitates formation.Precipitation can be either beneficial or detrimental in alloys,thus it is important to control precipitates formation on purpose during alloy design.In this work,cluster-plus-glue-atom model(CGM)composition design method which is usually used to describe short-range order in traditional alloys has been successfully extended to MPEAs for precipitation design.The key challenge of extending CGM to MPEAs is the determination of center atom since there are no solvent or solute in MPEAs.Research has found that the element type of center atom was related not only with chemical affinity,but also with atomic volume difference in MPEAs,which has inevitable effect on atomic arrangement.Based on experimental data of MPEAs with precipitates,it was found that elements with either stronger chemical affinity or larger volume difference with other PEs would occupy the center site of clusters.Therefore,a cluster index(P_(C)),which considers both chemical affinity and atomic volume factors,was proposed to assist the determination of center atom in MPEAs.Based on the approach,a solid-solution Zr-Ti-V-Nb-Al BCC alloy was obtained by inhibiting the precipitation,while precipitation-strengthened Al-Cr-FeNi-V FCC alloy and Al-Co-Cr-Fe-Ni BCC alloy were designed by promoting the precipitation.Corresponding experimental results demonstrated that the approach could provide a relatively simple and accurate predication of precipitation and the compositions of precipitations were in line with PEs in cluster in MPEAs.The research may open an effective way for composition design of MPEAs with desired phase structure.展开更多
This paper intends to describe how to design an optimized and effective strategic information system （SIS） by using the existing resources under the new market circumstances in China. Some feasible methods are thus ...This paper intends to describe how to design an optimized and effective strategic information system （SIS） by using the existing resources under the new market circumstances in China. Some feasible methods are thus proposed, which are about the design of SIS by detailed analysis of the principle requirements. The paper also puts forward the architecture and configuration of SIS in China in general.展开更多
Nickel-based superalloys are indispensable for high-temperature engineering applications,yet their additive manufacturing(AM)is plagued by significant cracking defects.This review investigates crack failure mechanisms...Nickel-based superalloys are indispensable for high-temperature engineering applications,yet their additive manufacturing(AM)is plagued by significant cracking defects.This review investigates crack failure mechanisms in AM nickel-based superalloys,emphasizing methodologies to evaluate crack sensitivity and compositional design strategies to mitigate defects.Key crack types—solidification,liquation,solid-state,stress corrosion,fatigue,and creep-fatigue cracks—are analyzed,with focus on formation mechanisms driven by thermal gradients,solute segregation,and microstructural heterogeneities.Evaluation frameworks such as the Rappaz-Drezet-Gremaud(RDG)criterion,Solidification Cracking Index(SCI),and Strain Age Cracking(SAC)index are reviewed for predicting crack susceptibility through integration of thermodynamic parameters,solidification kinetics,and mechanical properties.Alloy compositional design strategies are presented,including optimization of strengthening elements(Al,Ti),grain boundary modifiers(B,Zr,Re),and impurity control(C,O),which suppress crack initiation and propagation via microstructure refinement and enhanced high-temperature resistance.Computational approaches,such as thermodynamically assisted design,high-throughput experimentation,and machine learning,are highlighted for decoding complex composition-structure-property relationships.Challenges in modeling multi-scale defect interactions and developing unified frameworks for manufacturing-and service-induced cracks are outlined.This review underscores the necessity of integrated computational-experimental strategies to advance reliable AM of nickel-based superalloys,providing insights for defect prediction,alloy optimization,and process control.展开更多
The growing demand for high-efficiency and low-loss energy conversion and transportation techniques urges the development of advanced Fe-Si based soft magnet alloys.Simultaneous achievement of low coercivity(Hc)and la...The growing demand for high-efficiency and low-loss energy conversion and transportation techniques urges the development of advanced Fe-Si based soft magnet alloys.Simultaneous achievement of low coercivity(Hc)and large saturation magnetization(Ms)however,remains challenging.In this study,soft magnetic alloys with the composition Fe82-xSi18Cox(x=0 at.%,4 at.%,8 at.%,12 at.%,16 at.%,and 20 at.%)have been designed followed by microstructural tuning.The Co incorporation results in initially decreased Hc followed by increment due to reduced magnetocrystalline anisotropy and increased saturation mag-netostriction from negative to positive values of the alloys.Meanwhile,the Ms raises with subsequent reduction,which origins from competitive mechanisms of increased average moment of Fe atoms and decreased average moment of Co atoms according to first principles calculations.Microstructural evolu-tion during annealing of the Fe70Si18C012 with synergistically optimized Hc and Ms has been revealed that after elevated-temperature annealing,the DO3 phase is predominately transformed from the B2 phase ac-companied by an increase in the degree of ordering.The growth of the DO3 phase deteriorates the Hc due to the aggravating pinning effect on the domain wall movement,which arises from the inhomogeneous magnetization distribution caused by increasing antiphase boundaries.展开更多
Ni-based superalloys play a critical role in the aerospace industry due to their exceptional mechanical properties and oxidation resistance.However,the conventional development of new superalloys is often constrained ...Ni-based superalloys play a critical role in the aerospace industry due to their exceptional mechanical properties and oxidation resistance.However,the conventional development of new superalloys is often constrained by lengthy experimental cycles and high costs.To address these challenges,machine learning has emerged as an effective strategy for accelerating alloy design by efficiently exploring composition-property relationship,optimizing processing parameters,and enhancing predictive accuracy.This review summarizes recent progress in applying machine learning to composition optimization and mechanical property prediction of Ni-based superalloys,emphasizing the integration of theoretical modeling and experimental validation.The importance of feature engineering,including data collection,preprocessing,feature construction,and dimensionality reduction,was first highlighted.Subsequently,the machine learning approaches for novel alloy design and prediction of key properties including fatigue resistance,creep resistance,and oxidation resistance were discussed.Through data-driven approaches,machine learning not only enhances predictive capabilities but also uncovers complex composition-property relationship,which accelerates the development of next-generation Ni-based superalloys.We anticipate that the continued advancements in this field will drive more efficient and cost-effective alloy design,ultimately accelerating the transition from computational predictions to experimental realizations.展开更多
Determining the optimal ceramic content of the ceramics-in-polymer composite electrolytes and the appropriate stack pressure can effectively improve the interfacial contact of solid-state batteries(SSBs).Based on the ...Determining the optimal ceramic content of the ceramics-in-polymer composite electrolytes and the appropriate stack pressure can effectively improve the interfacial contact of solid-state batteries(SSBs).Based on the contact mechanics model and constructed by the conjugate gradient method,continuous convolution,and fast Fourier transform,this paper analyzes and compares the interfacial contact responses involving the polymers commonly used in SSBs,which provides the original training data for machine learning.A support vector regression model is established to predict the relationship between the content of ceramics and the interfacial resistance.The Bayesian optimization and K-fold cross-validation are introduced to find the optimal combination of hyperparameters,which accelerates the training process and improves the model’s accuracy.We found the relationship between the content of ceramics,the stack pressure,and the interfacial resistance.The results can be taken as a reference for the design of the low-resistance composite electrolytes for solid-state batteries.展开更多
Aluminum alloys with ultra-strength and high-toughness are fundamental structural materials applied in the aerospace industry.Due to the intrinsic restriction between strength and toughness,optimizing a desirable comb...Aluminum alloys with ultra-strength and high-toughness are fundamental structural materials applied in the aerospace industry.Due to the intrinsic restriction between strength and toughness,optimizing a desirable combination of these conflicting properties is always challenging in material development.In this study,171 sets of data were curated based on the characteristics of high-strength and high-toughness aluminum alloys in the literature.Then,a machine learning design system(MLDS)with a property-oriented design strategy was established to rapidly discover novel aluminum alloys with ductility and toughness indexes(with elongationδ=8%–10%and fracture toughness K_(IC)=33–35 MPa·m^(1/2))comparable to those of current state-of-the-art AA7136 aluminum alloys when the ultimate tensile strength(UTS)exceeded approximately 100 MPa,with values reaching 700–750 MPa.With the MLDS for experimental verification,three typical candidate alloys show satisfactory performance with UTS of 707–736 MPa,δof 7.8%–9.5%,and K_(IC)of 32.2–33.9 MPa·m^(1/2).The high contents of Mg and Zn alloying elements in the novel alloys form abundantη'phases,which produce a significant hardening effect,while the reasonable matching of Cr,Mn,Ti and Zr dispersoids refines the grain size.The decreased Cu content compared with that in the AA7136 alloy inhibits the formation of theσphase and S phase,so that the alloys show high toughness.展开更多
In this study,α+βTi-Al-V-Mo-Nb alloys with the addition of multiple elements that are suitable for laser additive manufacturing(LAM)were designed according to a Ti-6Al-4V cluster formula.This formula can be expresse...In this study,α+βTi-Al-V-Mo-Nb alloys with the addition of multiple elements that are suitable for laser additive manufacturing(LAM)were designed according to a Ti-6Al-4V cluster formula.This formula can be expressed as 12[Al-Ti12](AlTi2)+5[Al-Ti14]((Mo,V,Nb)2Ti),in which Mo and Nb were added into the alloys partially instead of V to give alloys with nominal compositions of Ti-6.01Al-3.13V-1.43Nb,Ti-5.97Al-2.33V-2.93Mo,and Ti-5.97Al-2.33V-2.20Mo-0.71Nb(wt.%).The microstructures and mechanical properties of the as-deposited and heat-treated samples prepared via LAM were examined.The sizes of theβcolumnar grains andαlaths in the Nb-containing samples are found to be larger than those of the Ti-6Al-4V alloy,whereas Mo-or Mo/Nb-added alloys contain finer grains.It indicates that Nb gives rise to coarsenedβcolumnar grains andαlaths,while Mo significantly refines them.Furthermore,the single addition of Nb improves the elongation,whereas the single addition of Mo enhances the strength of the alloys.The simultaneous addition of Mo/Nb significantly improves the comprehensive mechanical properties of the alloys,leading to the best properties with an ultimate tensile strength of 1,070 MPa,a yield strength of 1,004 MPa,an elongation of 9%,and micro-hardness of 355 HV.The fracture modes of all the alloys are ductile-brittle mixed fracture.展开更多
The photocatalytic degradation kinetics of carbofuran was optimized by central composite design based on response surface methodology for the first time. Three variables, TiO2 concentration, initial pH value and the c...The photocatalytic degradation kinetics of carbofuran was optimized by central composite design based on response surface methodology for the first time. Three variables, TiO2 concentration, initial pH value and the concentration of carbofuran, were selected to determine the dependence of degradation efficiencies on independent variables. Response surface methodology modeling results indicated that the degradation efficiency of carbofuran was highly affected by the initial pH value and the concentration of carbofuran. Then nine degradation intermediates were detected by HPLC/MS/MS. The Frontier Electron Densities of carbofuran were calculated to predict the active sites on carbofuran attacked by hydroxyl radicals and photoholes. Point charges were used to elucidate the chemisorption pattern on TiO2 catalysts during the photocatalytic process. By combining the experimental results and calculation data, the photocatalytic degradation pathways of carbofuran were proposed, including the addition of hydroxyl radicals and the cleavage of the carbamate side chain.展开更多
Oscillating heat pipes (OHPs) are very promising cooling devices. Their heat transfer performance is af- fected by many factors, and the form of the relationship between the performance and the factors is complex and ...Oscillating heat pipes (OHPs) are very promising cooling devices. Their heat transfer performance is af- fected by many factors, and the form of the relationship between the performance and the factors is complex and non-linear. In this paper, the effects of charging ratio, inclination angle, and heat input and their interaction effects on heat transfer performance of a looped copper-water OHP are analyzed. First, suppose that the relationship between the response and the variables approximates a second-order model. And use the central composite design to arrange the ex- periment. Then, the method of least squares is used to estimate the parameters in the second-order model. Finally, multi- variate variance analysis is used to analyze the model. The results show that the assumption is right, that is to say, the re- lationship is well modeled by a second-order function. Among the three main effect variables, the effect of inclination angle is the most significant, but their interaction effects are not significant. In the range of the considered factors, both the optimum charging ratio and the optimum inclination angle increase as the heating water flow rate increases.展开更多
Different multidisciplinary design optimization （MDO） problems are formulated and compared. Two MDO formulations are applied to a sounding rocket in order to optimize the performance of the rocket. In the MDO of the...Different multidisciplinary design optimization （MDO） problems are formulated and compared. Two MDO formulations are applied to a sounding rocket in order to optimize the performance of the rocket. In the MDO of the referred vehicle, three disciplines have been considered, which are trajectory, propulsion and aerodynamics. A special design structure matrix is developed to assist data exchange between disciplines. This design process uses response surface method （RSM） for multidisciplinary optimization of the rocket. The RSM is applied to the design in two categories： the propulsion model and the system level. In the propulsion model, RSM determines an approximate mathematical model of the engine output parameters as a function of design variables. In the system level, RSM fits a surface of objective function versus design variables. In the first MDO problem formulation, two design variables are selected to form propulsion discipline. In the second one, three new design variables from geometry are added and finally, an optimization method is applied to the response surface in the system level in order to find the best result. Application of the first developed multidisciplinary design optimization procedure increased accessible altitude （performance index） of the referred sounding rocket by twenty five percents and the second one twenty nine.展开更多
基金2023 Kashi University Level Teaching and Research Reform Project(KJDY2310)2024 Kashi University Level Research Project(2024-12005)Special Project on Education and Teaching Reform of Jiangxi University of Engineering(2021-JGJGZX-20)。
文摘This paper endeavors to explore the integration of curriculum ideological and political elements into the blended teaching of the Design Composition course based on the OBE(outcome-based education)concept.It analyzes the implementation paths and practical effects,providing a reference for the integration of ideological and political education and professional education in art design education in the new era.By analyzing the core content of the OBE concept in combination with the characteristics of the Design Composition course,we discuss the integration of ideological and political elements into teaching design.Employing methods of case analysis and literature review,and in conjunction with the blended teaching mode,we design a teaching process that conforms to the OBE concept,optimize practical activities and evaluation systems,and enhance students’ideological and moral qualities as well as disciplinary accomplishments.The research reveals that through the integration of ideological and political education in courses based on the OBE concept,it is possible to not only improve students’professional skills but also enhance their sense of social responsibility and cultural confidence.
基金National Natural Science Foundation of China(U22A20191)。
文摘Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects.
基金financially supported by the National Key R&D Program of China(No.2021YFC2202300)the National Natural Science Foundation of China(NSFC)(No.51974258)the National College Students Innovation and Entrepreneurship Training Program(No.S202210699134).
文摘Gold-platinum(Au-Pt)alloy has aroused considerable attention due to its ultra-low magnetic susceptibility(MS)in testing mass(TM)on spacecraft.However,the effect of Au content on the properties of the alloy has not yet been understood.In this study,the composition design of Au-Pt alloy with ultra-low MS was achieved through density functional theory(DFT)and experimental methods.The elastic,thermal properties and electronic structure were systematically investigated,the composition range was further optimized and Au75Pt25 was determined to be the most suitable alloy for TM material.The phase composition of this alloy after cold rolling and solid solution was characterized,indicating a single-phase FCC structure.In addition,there is a good validation between the experimental Vickers hardness and the DFT results.This work provides new insights into the compositional optimization of Au-Pt alloys and lays the foundation for alloy development.
文摘The solidification paths of Al-Zn-Mg-Cu alloys and its precipitation behavior are analyzed using software package JMatPro 6.0 for material property simulation of Al-base alloys.The microstructures of the experimental alloys are analyzed;the experimental results of microstructural analysis are in agreement with the thermodynamic prediction.Through orthogonal experimental method,this paper designs the composition of Al-Zn-Mg-Cu alloys by studying the variation of η(MgZn2) phase,S(Al2CuMg) phase,T(AlZnMgCu) phase amount and precipitation temperatures with different Zn,Mg and Cu contents.It is found that with the optimum mass fraction of Zn of 6.7%,Mg of 2.2%-2.5% and Cu of 1.6%-2.0%,the mass fraction of η phase can be up to 8.7%-9.22% and that of S phase and T phase can be lower than 0.5%.
文摘The improvement of machining behavior of prehardened-mould steel for plastic is realized by using computer-aided composition design in this work. The results showed that the matrix composition of large sectional prehardened mould steel for plastic markedly influences the precipitation of non-metallic inclusion and the control of composition aided by Thermo-Calc software package minimizes the amount of detrimental oxide inclusion. In addition the modification of calcium is optimized in the light of composition design.
文摘Theempiricalelectrontheory of solidsand molecules( EET) and theimproved TFDtheory wereapplied tocalculatethe phasestructurefactorsand interfaceconjunction factorsofcom mon alloying elementsincastiron. Akind of Si- Mo- Cu ductileiron with rareearth Mg asnodularizer was designed accordingtothese valenceelectron structure parameters. Actual applicationtestsshow thatthelongevity of thisiron is 1.5 timesof thatof high manganesesteel. This accordance of theoretical results and actual effectsshows the composition design methodcan beused in othercastiron research.
基金the Science and Technology Foundation of Retuned Students Studying Abroad of Shanxi Province of China(No. 1995-26)
文摘For austenitic octahedral segregation structure units, their pure mathematics statistic distribu!ive probability is calculated by the empirical electron theory （EET） of solids and molecules and K-B formula. The practical distributive probability can be obtained only if the statistic distribution of austenitic octahedral segregation structure units and the interaction of the alloying elements in steel are considered. Based on 8 groups of experimental data of original steels, three empirical formulas revealing relationships between material macromechanics factor （Sm） and tensile strength （ab）, or impact energy （AK）, or hardness （HRC） of multi-component medium-low-alloy steels were established, respectively. Through the three empirical formulas, new supersaturated carburizing steel has been successfully designed and developed. The other 2 groups of the original experimental steels are used as the standard steel for testing the percentage error of the new steel. The results show that the calculated values are well consistent with those of measured ones and the new supersaturated carburized steel can meet the requirements of the die assembly of cold-drawn seamless stainless steel tube of Taiyuan Iron ＆ Steel （Group） Company LTD.
文摘Erratum to:International Journal of Minerals, Metallurgy and Materials Volume 26, Number 9, September 2019, Page 1151https://doi.org/10.1007/s12613-019-1854-1The original version of this article unfortunately contained a mistake. The presentation of Fig. 11 was incorrect. The correct version is given below:
文摘The composition of a bearing steel was designed for limited hardenability by use of Grossmann's method. A medium frequency induction Process was applied to heat bearings to ensure penetrant heating and suitable solving of carbon and other elements in the matrix. The hardened depth measured from the end quenching test samples and actual bearings matches well with the designed one.
基金financially supported by the China Postdoctoral Science Foundation(No.2019M660482)Use of the Advanced Photon Source is supported by the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences,under Contract No.DE-AC02-06CH11357。
文摘Multi-principal element alloys(MPEAs)have shown extraordinary properties in different fields.However,the composition design of MPEAs is still challenging due to the complicated interactions among principal elements(PEs),and even more challenging with precipitates formation.Precipitation can be either beneficial or detrimental in alloys,thus it is important to control precipitates formation on purpose during alloy design.In this work,cluster-plus-glue-atom model(CGM)composition design method which is usually used to describe short-range order in traditional alloys has been successfully extended to MPEAs for precipitation design.The key challenge of extending CGM to MPEAs is the determination of center atom since there are no solvent or solute in MPEAs.Research has found that the element type of center atom was related not only with chemical affinity,but also with atomic volume difference in MPEAs,which has inevitable effect on atomic arrangement.Based on experimental data of MPEAs with precipitates,it was found that elements with either stronger chemical affinity or larger volume difference with other PEs would occupy the center site of clusters.Therefore,a cluster index(P_(C)),which considers both chemical affinity and atomic volume factors,was proposed to assist the determination of center atom in MPEAs.Based on the approach,a solid-solution Zr-Ti-V-Nb-Al BCC alloy was obtained by inhibiting the precipitation,while precipitation-strengthened Al-Cr-FeNi-V FCC alloy and Al-Co-Cr-Fe-Ni BCC alloy were designed by promoting the precipitation.Corresponding experimental results demonstrated that the approach could provide a relatively simple and accurate predication of precipitation and the compositions of precipitations were in line with PEs in cluster in MPEAs.The research may open an effective way for composition design of MPEAs with desired phase structure.
文摘This paper intends to describe how to design an optimized and effective strategic information system （SIS） by using the existing resources under the new market circumstances in China. Some feasible methods are thus proposed, which are about the design of SIS by detailed analysis of the principle requirements. The paper also puts forward the architecture and configuration of SIS in China in general.
基金supported by the Aero Engine Corporation of China[Grant No.HFZL2022CXY029]the Young Elite Scientists Sponsorship Programby CAST[2022QNRC001]the High Performance Computing Center of Central South University,and the Project Supported by State Key Laboratory of Powder Metallurgy,Central South University,Changsha,China。
文摘Nickel-based superalloys are indispensable for high-temperature engineering applications,yet their additive manufacturing(AM)is plagued by significant cracking defects.This review investigates crack failure mechanisms in AM nickel-based superalloys,emphasizing methodologies to evaluate crack sensitivity and compositional design strategies to mitigate defects.Key crack types—solidification,liquation,solid-state,stress corrosion,fatigue,and creep-fatigue cracks—are analyzed,with focus on formation mechanisms driven by thermal gradients,solute segregation,and microstructural heterogeneities.Evaluation frameworks such as the Rappaz-Drezet-Gremaud(RDG)criterion,Solidification Cracking Index(SCI),and Strain Age Cracking(SAC)index are reviewed for predicting crack susceptibility through integration of thermodynamic parameters,solidification kinetics,and mechanical properties.Alloy compositional design strategies are presented,including optimization of strengthening elements(Al,Ti),grain boundary modifiers(B,Zr,Re),and impurity control(C,O),which suppress crack initiation and propagation via microstructure refinement and enhanced high-temperature resistance.Computational approaches,such as thermodynamically assisted design,high-throughput experimentation,and machine learning,are highlighted for decoding complex composition-structure-property relationships.Challenges in modeling multi-scale defect interactions and developing unified frameworks for manufacturing-and service-induced cracks are outlined.This review underscores the necessity of integrated computational-experimental strategies to advance reliable AM of nickel-based superalloys,providing insights for defect prediction,alloy optimization,and process control.
基金supported by the National Key R&D Program of China(No.2021YFB3501303)the National Natural Science Foundation of China(No.52122106)+3 种基金the"Pioneer"R&D Program of Zhejiang Province(No.2022C01230)"Leading Goose"R&D Program of Zhejiang Province(No.2022C01110)Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(No.2021SZ-FR005)the Space Application System of China Manned Space Program(No.KJZ-YY-NCL03).
文摘The growing demand for high-efficiency and low-loss energy conversion and transportation techniques urges the development of advanced Fe-Si based soft magnet alloys.Simultaneous achievement of low coercivity(Hc)and large saturation magnetization(Ms)however,remains challenging.In this study,soft magnetic alloys with the composition Fe82-xSi18Cox(x=0 at.%,4 at.%,8 at.%,12 at.%,16 at.%,and 20 at.%)have been designed followed by microstructural tuning.The Co incorporation results in initially decreased Hc followed by increment due to reduced magnetocrystalline anisotropy and increased saturation mag-netostriction from negative to positive values of the alloys.Meanwhile,the Ms raises with subsequent reduction,which origins from competitive mechanisms of increased average moment of Fe atoms and decreased average moment of Co atoms according to first principles calculations.Microstructural evolu-tion during annealing of the Fe70Si18C012 with synergistically optimized Hc and Ms has been revealed that after elevated-temperature annealing,the DO3 phase is predominately transformed from the B2 phase ac-companied by an increase in the degree of ordering.The growth of the DO3 phase deteriorates the Hc due to the aggravating pinning effect on the domain wall movement,which arises from the inhomogeneous magnetization distribution caused by increasing antiphase boundaries.
基金financially supported by the National Natural Science Foundation of China(Nos.52201203 and 52471004)the Fundamental Research Funds for the Central Universities(No.N2423030)the Science and Technology Project of Hebei Education Department(No.QN2023155).
文摘Ni-based superalloys play a critical role in the aerospace industry due to their exceptional mechanical properties and oxidation resistance.However,the conventional development of new superalloys is often constrained by lengthy experimental cycles and high costs.To address these challenges,machine learning has emerged as an effective strategy for accelerating alloy design by efficiently exploring composition-property relationship,optimizing processing parameters,and enhancing predictive accuracy.This review summarizes recent progress in applying machine learning to composition optimization and mechanical property prediction of Ni-based superalloys,emphasizing the integration of theoretical modeling and experimental validation.The importance of feature engineering,including data collection,preprocessing,feature construction,and dimensionality reduction,was first highlighted.Subsequently,the machine learning approaches for novel alloy design and prediction of key properties including fatigue resistance,creep resistance,and oxidation resistance were discussed.Through data-driven approaches,machine learning not only enhances predictive capabilities but also uncovers complex composition-property relationship,which accelerates the development of next-generation Ni-based superalloys.We anticipate that the continued advancements in this field will drive more efficient and cost-effective alloy design,ultimately accelerating the transition from computational predictions to experimental realizations.
基金the National Natural Science Foundation of China(12102085)the Postdoctoral Science Foundation of China(2023M730504)the Sichuan Province Regional Innovation and Cooperation Project(2024YFHZ0210).
文摘Determining the optimal ceramic content of the ceramics-in-polymer composite electrolytes and the appropriate stack pressure can effectively improve the interfacial contact of solid-state batteries(SSBs).Based on the contact mechanics model and constructed by the conjugate gradient method,continuous convolution,and fast Fourier transform,this paper analyzes and compares the interfacial contact responses involving the polymers commonly used in SSBs,which provides the original training data for machine learning.A support vector regression model is established to predict the relationship between the content of ceramics and the interfacial resistance.The Bayesian optimization and K-fold cross-validation are introduced to find the optimal combination of hyperparameters,which accelerates the training process and improves the model’s accuracy.We found the relationship between the content of ceramics,the stack pressure,and the interfacial resistance.The results can be taken as a reference for the design of the low-resistance composite electrolytes for solid-state batteries.
基金supported by the National Natural Science Foundation of China(Nos.52090041,51921001,52022011)the Beijing Municipal Science and Technology Commission(Nos.Z191100007219002,Z191100001119125)the Key Scientific and Technological Project of Foshan City(No.1920001000409)
文摘Aluminum alloys with ultra-strength and high-toughness are fundamental structural materials applied in the aerospace industry.Due to the intrinsic restriction between strength and toughness,optimizing a desirable combination of these conflicting properties is always challenging in material development.In this study,171 sets of data were curated based on the characteristics of high-strength and high-toughness aluminum alloys in the literature.Then,a machine learning design system(MLDS)with a property-oriented design strategy was established to rapidly discover novel aluminum alloys with ductility and toughness indexes(with elongationδ=8%–10%and fracture toughness K_(IC)=33–35 MPa·m^(1/2))comparable to those of current state-of-the-art AA7136 aluminum alloys when the ultimate tensile strength(UTS)exceeded approximately 100 MPa,with values reaching 700–750 MPa.With the MLDS for experimental verification,three typical candidate alloys show satisfactory performance with UTS of 707–736 MPa,δof 7.8%–9.5%,and K_(IC)of 32.2–33.9 MPa·m^(1/2).The high contents of Mg and Zn alloying elements in the novel alloys form abundantη'phases,which produce a significant hardening effect,while the reasonable matching of Cr,Mn,Ti and Zr dispersoids refines the grain size.The decreased Cu content compared with that in the AA7136 alloy inhibits the formation of theσphase and S phase,so that the alloys show high toughness.
基金the National Key Research and Development Program of China(No.2016YFB1100103)the Key Discipline and Major Project of Dalian Science and Technology Innovation Foundation(No.2020JJ25CY004)。
文摘In this study,α+βTi-Al-V-Mo-Nb alloys with the addition of multiple elements that are suitable for laser additive manufacturing(LAM)were designed according to a Ti-6Al-4V cluster formula.This formula can be expressed as 12[Al-Ti12](AlTi2)+5[Al-Ti14]((Mo,V,Nb)2Ti),in which Mo and Nb were added into the alloys partially instead of V to give alloys with nominal compositions of Ti-6.01Al-3.13V-1.43Nb,Ti-5.97Al-2.33V-2.93Mo,and Ti-5.97Al-2.33V-2.20Mo-0.71Nb(wt.%).The microstructures and mechanical properties of the as-deposited and heat-treated samples prepared via LAM were examined.The sizes of theβcolumnar grains andαlaths in the Nb-containing samples are found to be larger than those of the Ti-6Al-4V alloy,whereas Mo-or Mo/Nb-added alloys contain finer grains.It indicates that Nb gives rise to coarsenedβcolumnar grains andαlaths,while Mo significantly refines them.Furthermore,the single addition of Nb improves the elongation,whereas the single addition of Mo enhances the strength of the alloys.The simultaneous addition of Mo/Nb significantly improves the comprehensive mechanical properties of the alloys,leading to the best properties with an ultimate tensile strength of 1,070 MPa,a yield strength of 1,004 MPa,an elongation of 9%,and micro-hardness of 355 HV.The fracture modes of all the alloys are ductile-brittle mixed fracture.
基金supported by the National Natural Science Foundation of China (No.21207034, 21172064)the Provincial Natural Science Foundation of Hunan (No.10JJ2006)the Key Scientific Research Fund of Hunan Provincial Education Department (No.10A022)
文摘The photocatalytic degradation kinetics of carbofuran was optimized by central composite design based on response surface methodology for the first time. Three variables, TiO2 concentration, initial pH value and the concentration of carbofuran, were selected to determine the dependence of degradation efficiencies on independent variables. Response surface methodology modeling results indicated that the degradation efficiency of carbofuran was highly affected by the initial pH value and the concentration of carbofuran. Then nine degradation intermediates were detected by HPLC/MS/MS. The Frontier Electron Densities of carbofuran were calculated to predict the active sites on carbofuran attacked by hydroxyl radicals and photoholes. Point charges were used to elucidate the chemisorption pattern on TiO2 catalysts during the photocatalytic process. By combining the experimental results and calculation data, the photocatalytic degradation pathways of carbofuran were proposed, including the addition of hydroxyl radicals and the cleavage of the carbamate side chain.
基金Supported by the Natural Science Foundation of Ministry of Education of Jiangsu Province (02KJB470001).
文摘Oscillating heat pipes (OHPs) are very promising cooling devices. Their heat transfer performance is af- fected by many factors, and the form of the relationship between the performance and the factors is complex and non-linear. In this paper, the effects of charging ratio, inclination angle, and heat input and their interaction effects on heat transfer performance of a looped copper-water OHP are analyzed. First, suppose that the relationship between the response and the variables approximates a second-order model. And use the central composite design to arrange the ex- periment. Then, the method of least squares is used to estimate the parameters in the second-order model. Finally, multi- variate variance analysis is used to analyze the model. The results show that the assumption is right, that is to say, the re- lationship is well modeled by a second-order function. Among the three main effect variables, the effect of inclination angle is the most significant, but their interaction effects are not significant. In the range of the considered factors, both the optimum charging ratio and the optimum inclination angle increase as the heating water flow rate increases.
文摘Different multidisciplinary design optimization （MDO） problems are formulated and compared. Two MDO formulations are applied to a sounding rocket in order to optimize the performance of the rocket. In the MDO of the referred vehicle, three disciplines have been considered, which are trajectory, propulsion and aerodynamics. A special design structure matrix is developed to assist data exchange between disciplines. This design process uses response surface method （RSM） for multidisciplinary optimization of the rocket. The RSM is applied to the design in two categories： the propulsion model and the system level. In the propulsion model, RSM determines an approximate mathematical model of the engine output parameters as a function of design variables. In the system level, RSM fits a surface of objective function versus design variables. In the first MDO problem formulation, two design variables are selected to form propulsion discipline. In the second one, three new design variables from geometry are added and finally, an optimization method is applied to the response surface in the system level in order to find the best result. Application of the first developed multidisciplinary design optimization procedure increased accessible altitude （performance index） of the referred sounding rocket by twenty five percents and the second one twenty nine.
