应力三轴度对TA31钛合金失效行为的影响研究  

Effect of stress triaxiality on the failure behavior of TA31 titanium alloy

作　　者：张博文[1,2] 万正权 张爱锋[1,2] 于翔宇 徐强[1,2] ZHANG Bo-wen;WAN Zheng-quan;ZHANG Ai-feng;YU Xiang-yu;XU Qiang(China Ship Scientific Research Center,Wuxi 214082,China;Taihu Laboratory of Deepsea Technological Science,Wuxi 214082,China)

机构地区：[1]中国船舶科学研究中心,江苏无锡214082 [2]深海技术科学太湖实验室,江苏无锡214082

出　　处：《船舶力学》2022年第10期1485-1495,共11页Journal of Ship Mechanics

基　　金：江苏省自然科学基金资助项目(BK20190152)。

摘　　要：TA31钛合金由于其塑韧性高、可焊性好等优点,已成为深海装备的优先选用材料之一。本文以TA31钛合金为研究对象,首先开展典型钛合金试件的断裂性能试验,分析应力三轴度等参量对TA31钛合金断裂性能的影响规律,借助扫描电镜对试件的断后形态进行断口分析,阐明TA31钛合金在复杂应力状态下的断裂失效机理。然后,在Johnson-Cook模型中引入平均应力三轴度参数的影响,形成计及应力状态参量影响的本构关系模型,通过试件试验数据进行模型参数校准,建立适用于复杂应力状态下的TA31钛合金塑性硬化模型,并将该模型扩展应用于深潜器耐压球壳结构极限承载能力的评估中。本研究可为深海装备钛合金结构设计与评估提供研究基础。TA31 titanium alloy is one of the preferred materials for deep-sea equipment due to its high plas⁃ticity,high fracture toughness and good weldability.This paper presents the fracture behavior tests of typical titanium alloy specimens carried out to investigate the influence of stress triaxiality on the fracture properties of TA31 titanium alloy.The fracture surface of the specimen was analyzed by scanning electron microscope to elucidate the failure mechanism of titanium alloy under complex stress state.The expression of average stress triaxiality was introduced in the Johnson-Cook model to take account of the influence of stress state parame⁃ters on constitutive relationships.The model parameters were calibrated based on the test data,and the modi⁃fied Johnson-Cook model for TA31 titanium alloy was established.Furthermore,the new model was extended to evaluate the pressure hull ultimate strength of deep-sea submersibles.The research results in this paper can provide a research basis for the design and evaluation of titanium alloy structures of deep-sea equipment.

关 键 词：TA31钛合金 硬化模型 应力三轴度 耐压球壳 极限承载能力 

分 类 号：U663.1[交通运输工程—船舶及航道工程] U668.1[交通运输工程—船舶与海洋工程]