Phase-Field Modeling of Microstructural Evolutions in Cu-Ag Alloys during Aging Process

摘要：

The phase decompositions and the microstructure developments in Cu-20 and 40 at.％ Ag alloys during isothermal aging have been quantitatively simulated based on the phase-field method. Contributions to the free energy of the system from bulk chemical mixing energy, concentration gradient energy and coherent misfit strain energy were incorporated. In the calculations, the chemical free energy used was obtained from the thermodynamic database of phase diagrams, therefore the calculated microstructure changes were directly related to the phase diagram of the real alloy system. The morphologies and the composition profiles of the alloys were obtained as a function of time, temperature and component concentrations. The simulation results show that both the decomposing and coarsening speeds of the symmetric alloy (Cu-40 ％at Ag) are faster than that corresponding to the asymmetric alloy. The early stages of phase separation in the symmetric alloy always result in a regular and interconnected morphology. The Ag precipitations in Cu-20 at.％ Ag alloy during aging undergo a process including spinodal decomposition and coarsening, and change to a cuboid shape aligned along the 100 direction.

关键词： phase-field method spinodal decomposition microstructural evolution morphology

作者: LONG Yong-qiang LIU Ping LIU Yong JIA Shu-guo TIAN Bao-hong

作者单位: School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang,China College of Mechanical Engineering,University of Shanghai for Science and Technology,Shanghai,China 2 School of Materials Science and Engineering,Henan University of Science and Technology, Luoyang,Chin School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang,China

会议类型: 国际会议

会议名称: The Fourth Asian Conference on Heat Treatment and Surface Engineering(第四届亚洲热处理及表面工程大会)

会议地点: 北京

会议语种:英文

页码: 458-462

在线出版日期: 2009-10-27（万方平台首次上网日期，不代表论文的发表时间）