摘要
基于晶体塑性理论,建立了滑移变形机制下Ti_3Al单晶晶体塑性的细观本构关系,并利用ABAQUS/UMAT用户子程序接口开发本构关系子程序,将其应用于不同取向Ti_3Al单晶的单向压缩模拟。分析不同取向时晶体滑移系的启动情况,以及滑移系启动与取向的相互关系。结果表明:基面滑移系(0001)<1120>,柱面滑移系{1010}<1120>和锥面滑移系{1121}<1126>均被激活,但由于滑移系之间临界剪切应力和施密特因子的不同,各滑移系的启动情况存在显著差异。基面和锥面滑移系的临界剪切应力较大,仅在施密特因子较大时启动;特别是锥面滑移系,其临界剪切应力最大,因而该滑移系只有在压缩轴接近[0001]方向时才被激活。柱面滑移系的启动较为容易,对塑性变形的贡献也最大。同时与实验结果相比较,模拟结果基本与之吻合。
A crystal plasticity constitutive model for Ti3Al single crystal was established based on slip deformation mechanism within the frame of crystal plasticity theory, and a program was compiled to describe it by means of secondary development of ABAQUS/UMAT user subroutine. Then we applied it to simulate the mechanical behaviors of Ti3Al single crystal with different orientations during unidirectional compression deformation. The activation of slip systems and the interaction between activation and orientation has been analyzed. The simulation results show that basal slip of（0001）11 20, prismatic slip of {1010}1120, and pyramidal slip of {11 21}1126 can be activated. However, there is dramatic difference on the ease or complexity of activation of various slip systems, which is due to the difference of critical shear stress and Schmid factor. It is difficult for basal slip and pyramidal slip to be activated because of their larger critical shear stress, which causes the activation of basal slip and pyramidal slip just with a larger Schmid factor. Pyramidal slip systems can be initiated only when compression axis is close to [0001] direction due to the maximum critical shear stress. Prismatic slip is much easier to be activated and also has the largest contribution to plastic deformation. Furthermore, the simulation results are in good agreement with the experimental results.
作者
赵文娟
唐安
林启权
任玉平
徐俊瑞
宋滨娜
Zhao Wenjuan;Tang An;Lin Qiquan;Ren Yuping;Xu Junrui;Song Binna(Xiangtan University, Xiangtan 411105, China;Northeastern University, Shenyang 110819, China;Soochow University, Suzhou 215021, China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2018年第6期1753-1759,共7页
Rare Metal Materials and Engineering
基金
国家自然科学基金(51175445
51201147
51304141)
湖南省自然科学基金(14JJ6016)
关键词
Ti3Al单晶
晶体塑性
位错
滑移系
有限元
本构关系
Ti3Al single crystal
crystal plasticity
dislocation
slip system
finite element
constitutive relationship
