X-ray computed tomography(XCT)has recently emerged as a powerful tool for characterizing the evolution of microstructure during phase transformation in three dimensional(3D)such as dendritic solidification of alloys.T...X-ray computed tomography(XCT)has recently emerged as a powerful tool for characterizing the evolution of microstructure during phase transformation in three dimensional(3D)such as dendritic solidification of alloys.This paper briefly reviews the recent advances in the in-situ observation of aluminium alloys,magnesium alloys and nickel-based superalloys during solidification using laboratory XCT and synchrotron X-ray sources.The focus is on the growth kinetics of dendrites,porosity and secondary phases.In addition,in-situ characterization during the loading and corrosion process is also discussed.展开更多
A multi-phase-field model is implemented to investigate the peritectic solidification of Fe-C alloy. The nucleation mode of austenite is based on the local driving force, and two different thicknesses of the primary a...A multi-phase-field model is implemented to investigate the peritectic solidification of Fe-C alloy. The nucleation mode of austenite is based on the local driving force, and two different thicknesses of the primary austenite on the surface of the ferrite equiaxed crystal grain are used as the initial conditions. The simulation shows the multiple interactions of ferrite, austenite, and liquid phases, and the effects of carbon diffusion, which presents the non-equilibrium dynamic process during Fe-C peritectic solidification at the mesoscopic scale. This work not only reveals the influence of the austenite nucleation position, but also clarifies the formation mechanism of liquid phase channels and molten pools. Therefore, the present study contributes to the understanding of the micro-morphology and micro-segregation evolution mechanisms of Fe-C alloy during peritectic solidification.展开更多
Integrated computational materials engineering(ICME)has emerged to be one of the most powerful materials genome engineering(MGE)approaches in designing new materials and manufacturing processes in recent years.It has ...Integrated computational materials engineering(ICME)has emerged to be one of the most powerful materials genome engineering(MGE)approaches in designing new materials and manufacturing processes in recent years.It has successfully deployed many new products for the electronic,automotive,and aerospace industries.This paper reviews the current status of research on first principles in the design of high-strength Mg alloys,discusses the application of crystal plasticity finite element models to the microscale slip,twinning,microstructure morphology,texture evolution,and macroscopic forming of Mg alloys,and introduces the research progress of crystal plasticity finite element models and phase field models,meta cellular automata models and first principles coupled models respectively,around the need for multi-scale coupled simulations of Mg alloys.The key technology obstacles of integrating the first principles,crystal plasticity finite element,and microstructure models for Mg alloys have been solved.This paper can provide a reference for the design of new Mg alloy compositions and the development of high-performance Mg alloys.展开更多
Integrated computational materials engineering(ICME)is to integrate multi-scale computational simulations and key experimental methods such as macroscopic,mesoscopic,and microscopic into the whole process of Al alloys...Integrated computational materials engineering(ICME)is to integrate multi-scale computational simulations and key experimental methods such as macroscopic,mesoscopic,and microscopic into the whole process of Al alloys design and development,which enables the design and development of Al alloys to upgrade from traditional empirical to the integration of compositionprocess-structure-mechanical property,thus greatly accelerating its development speed and reducing its development cost.This study combines calculation of phase diagram(CALPHAD),Finite element calculations,first principle calculations,and microstructure characterization methods to predict and regulate the formation and structure of composite precipitates from the design of highmodulus Al alloy compositions and optimize the casting process parameters to inhibit the formation of micropore defects in the casting process,and the final tensile strength of Al alloys reaches420 MPa and Young's modulus reaches more than 88 GPa,which achieves the design goal of the high strength and modulus Al alloys,and establishes a new mode of the design and development of the strength/modulus Al alloys.展开更多
文摘X-ray computed tomography(XCT)has recently emerged as a powerful tool for characterizing the evolution of microstructure during phase transformation in three dimensional(3D)such as dendritic solidification of alloys.This paper briefly reviews the recent advances in the in-situ observation of aluminium alloys,magnesium alloys and nickel-based superalloys during solidification using laboratory XCT and synchrotron X-ray sources.The focus is on the growth kinetics of dendrites,porosity and secondary phases.In addition,in-situ characterization during the loading and corrosion process is also discussed.
基金Project supported by the Science Challenge Project,China(Grant No.TZZT2019-D1-03)the National Natural Science Foundation of China(Grant No.51972028)the National Key Research and Development Program of China(Grant No.2019YFA0307900)。
文摘A multi-phase-field model is implemented to investigate the peritectic solidification of Fe-C alloy. The nucleation mode of austenite is based on the local driving force, and two different thicknesses of the primary austenite on the surface of the ferrite equiaxed crystal grain are used as the initial conditions. The simulation shows the multiple interactions of ferrite, austenite, and liquid phases, and the effects of carbon diffusion, which presents the non-equilibrium dynamic process during Fe-C peritectic solidification at the mesoscopic scale. This work not only reveals the influence of the austenite nucleation position, but also clarifies the formation mechanism of liquid phase channels and molten pools. Therefore, the present study contributes to the understanding of the micro-morphology and micro-segregation evolution mechanisms of Fe-C alloy during peritectic solidification.
基金supported by National Natural Science Foundation of China(No.52073030)National Natural Science Foundation of China-Guangxi Joint Fund(No.U20A20276)。
文摘Integrated computational materials engineering(ICME)has emerged to be one of the most powerful materials genome engineering(MGE)approaches in designing new materials and manufacturing processes in recent years.It has successfully deployed many new products for the electronic,automotive,and aerospace industries.This paper reviews the current status of research on first principles in the design of high-strength Mg alloys,discusses the application of crystal plasticity finite element models to the microscale slip,twinning,microstructure morphology,texture evolution,and macroscopic forming of Mg alloys,and introduces the research progress of crystal plasticity finite element models and phase field models,meta cellular automata models and first principles coupled models respectively,around the need for multi-scale coupled simulations of Mg alloys.The key technology obstacles of integrating the first principles,crystal plasticity finite element,and microstructure models for Mg alloys have been solved.This paper can provide a reference for the design of new Mg alloy compositions and the development of high-performance Mg alloys.
基金supported by the National Natural Science Foundation of China(No.52073030)。
文摘Integrated computational materials engineering(ICME)is to integrate multi-scale computational simulations and key experimental methods such as macroscopic,mesoscopic,and microscopic into the whole process of Al alloys design and development,which enables the design and development of Al alloys to upgrade from traditional empirical to the integration of compositionprocess-structure-mechanical property,thus greatly accelerating its development speed and reducing its development cost.This study combines calculation of phase diagram(CALPHAD),Finite element calculations,first principle calculations,and microstructure characterization methods to predict and regulate the formation and structure of composite precipitates from the design of highmodulus Al alloy compositions and optimize the casting process parameters to inhibit the formation of micropore defects in the casting process,and the final tensile strength of Al alloys reaches420 MPa and Young's modulus reaches more than 88 GPa,which achieves the design goal of the high strength and modulus Al alloys,and establishes a new mode of the design and development of the strength/modulus Al alloys.