基于纳米压痕技术的Ti2AlNb焊接接头力学性能  

Mechanical Properties of Ti 2AlNb Welded Joints Based on Nano-indentation

作　　者：殷良伟 杨四辉 郭海丁 YIN Liangwei;YANG Sihui;GUO Haiding(Jiangsu Province Key Laboratory of Aerospace Power System,Nanjing 210016,China)

机构地区：[1]南京航空航天大学能源与动力学院江苏省航空动力系统重点实验室,江苏南京210016

出　　处：《材料科学与工程学报》2020年第3期397-402,487,共7页Journal of Materials Science and Engineering

摘　　要：焊接热过程产生的组织及相变会改变材料的力学性能,使接头不同微区之间产生力学性能不均匀性,对接头的破坏行为有重要影响。为获得Ti 2AlNb基合金电子束焊接头不同区域的力学性能,采用纳米压痕技术,通过对压头压入材料表面过程的有限元模拟,建立了压痕响应与焊接接头材料本构关系参数之间的无量纲函数,构建了一种逆向获得材料微区弹塑性本构关系的新方法。基于该方法反演获得了Ti 2AlNb电子束焊接头不同微区的本构关系参数及其分布,分析了组织变化对接头微区性能的影响及接头的弱化区间。Microstructure transition resulted from the welding thermal process often changes the mechanical properties and induces heterogeneity of the materials of the joint,which affects the failure behavior of the joints significantly.In order to acquire mechanical properties over the region of EBW(electronic beam welding)joint of Ti 2AlNb alloy,a reverse methodology was proposed to constitute dimensionless functions to characterize the indentation responses and the constitutive relationship parameters,in which nano-indentation were conducted for Ti 2AlNb EBW joint and FEM(finite element analysis)simulation for indentation process were made.The constitutive relationship parameters and their distributions in different zones of the joints were acquired.The influence of the microstructure variation on the mechanical properties of different zones of the joint was analyzed and the weak zones of the joint were identified.

关 键 词：纳米压痕技术 力学性能不均匀性 材料弹塑性性能反演 电子束焊 

分 类 号：V231.9[航空宇航科学与技术—航空宇航推进理论与工程]