51.1Zr-40.2Ti-4.5Al-4.2V合金拉伸变形过程中的组织演变和力学性能研究  

Microstructure Evolution and Mechanical Properties of 51.1Zr-40.2Ti-4.5Al-4.2V During Tensile Deformation

作　　者：杨秋月 谭元标 尹存宏[1,2] 刘文昌 向嵩[2] 赵飞[2] Yang Qiuyue;Tan Yuanbiao;Yin Cunhong;Liu Wenchang;Xiang Song;Zhao Fei(Key Laboratory of Modern Manufacturing Technology of Ministry of Education,Guizhou University,Guiyang 550025,China;Guizhou Key Laboratory of Materials Mechanical Behaviour and Microstructure,College of Materials and Metallurgy,Guizhou University,Guiyang 550025,China;Key Laboratory of Metastable Materials Science and Technology,College of Materials Science and Engineering,Yanshan University,Qinhuangdao 066004,China)

机构地区：[1]贵州大学现代制造技术教育部重点实验室,贵州贵阳550025 [2]贵州大学材料与冶金学院贵州省材料结构与强度重点实验室,贵州贵阳550025 [3]燕山大学材料科学与工程学院亚稳材料制备技术与科学国家重点实验室,河北秦皇岛066004

出　　处：《稀有金属材料与工程》2021年第1期320-326,共7页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51804087);贵州省联合基金([2017]5788,[2017]7240);贵州省科技计划项目(黔科合平台人才[2018]5781);贵州省基础研究计划项目(黔科合基础[2019]1091);贵州大学现代制造技术教育部重点实验室开放基金(XDKFJJ[2018]01)。

摘　　要：主要研究了51.1Zr-40.2Ti-4.5Al-4.2V合金室温拉伸变形过程中的组织演变和力学性能变化。研究表明,室温拉伸变形过程中合金发生从β相到α″相的转变,α″相的体积分数随拉伸速率的增加而减小。应力诱发α″马氏体相变对合金的力学行为有明显的影响。在拉伸速率为0.3 mm/min时,触发应力(TS),极限拉伸强度(UTS),延伸率(EL)和弹性模量(EM)分别为770.06 MPa,1168.60 MPa,14.96%和64 GPa。TS和EM随拉伸速率的增加而增加,而UTS和EL则降低。加工硬化率与真应变的关系曲线呈现出3个不同的阶段,应力诱发α″马氏体相变主要影响加工硬化率曲线的第2阶段。在给定应变条件下,第2阶段的加工硬化率随拉伸速率的增加逐渐降低。拉伸速率为0.3 mm/min时,合金的断口形貌是由大量韧窝以及少量准解理面组成的,合金发生塑性断裂,随着拉伸速率的增加,合金断裂方式由塑性断裂变为脆性断裂。这主要与应力诱发α″马氏体相含量随拉伸速率的增加而降低有关。The microstructure evolution and mechanical properties of 51.1Zr-40.2Ti-4.5Al-4.2V alloy during tensile deformation at room temperature were studied.The results show that the phase transformation fromβtoα″phase is observed in the process of tensile deformation at room temperature,and the volume fraction of theα″phase decreases with the increase of the tensile rate.The existence of theα″phase has an obvious effect on the mechanical properties of the alloy.At the tensile rate of 0.3 mm/min,the trigger stress(TS),ultimate tensile strength(UTS),elongation(EL)and elastic modulus(EM)are 770.06 MPa,1168.60 MPa,14.96%and 64 GPa,respectively.TS and EM increase with the increase of tensile rate,while UTS and EL decrease.Three different stages are presented in the curve of work hardening rate.Particularly,the second stage is affected by theα″phase.At a given strain,the work hardening rate at the second stage is gradually decreased with increasing the tensile rate.When the tensile rate is 0.3 mm/min,the fracture morphology of the alloy is composed of a large number of dimples and a small number of quasi-cleavage planes,which show a typical feature of plastic fracture.With the increase of the tensile rate,the fracture mode of the alloy changes from plastic fracture to brittle fracture.This is mainly due to the fact that the volume fraction of theα″phase decreases with the increase of the tensile rate.

关 键 词：ZrTiAlV合金 变形 应力诱发马氏体相变 加工硬化 

分 类 号：TG146.414[金属学及工艺—金属材料]