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基于极值理论的钛合金疲劳指数极大值分布研究与疲劳寿命预测
发布时间:2021-10-11 16:11:49 347

演讲人:谷瑭,哈尔滨工程大学副教授

题目:基于极值理论的钛合金疲劳指数极大值分布研究与疲劳寿命预测

时间:2021年10月13日,14:00~15:30

地点:T2306

内容摘要:

This work is related to Fatigue Indicator Parameters (FIPs) which are used as surrogate measures of the driving force for microscopic fatigue crack formation, and can then be used to estimate the minimum fatigue life of components. For a given microstructure, the Extreme Value Distribution (EVD) of FIPs can be populated using results of a number of digital Statistical Volume Element (SVE) instantiations analyzed by the crystal plasticity finite element method.The number of microstructure instantiations affects the maximum FIPs computed.To predict the EVD of the maximum FIPs in a large volume of interest using simulation results from a limited number of SVEs, we proposed a statistical approach based on extreme value theory.The predictions are compared directly to simulation results of 1000 SVEs to validate the proposed method.It is shown that simulations of only 100 SVEs suffice to identify the statistical information for a reliable prediction of the maximum FIPs in polycrystalline duplex Ti–6Al–4V with initial random texture.In this way, the required computational time can be minimized significantly. Finally, prediction of componentfatigue life is carried out, correlating with the EVD of the maximum FIPs in a low cycle fatigue regime.

 

个人简介:

谷瑭博士,2017年获法国国立巴黎高等矿业学校博士学位,后于美国亚特兰大佐治亚理工学院从事博士后工作;2021年至今,任哈尔滨工程大学机电工程学院副教授。谷瑭副教授在国立巴黎高等矿业学校就读博士期间,主要从事基于多尺度建模和表征实验的铜-铌复合线材力学电学性能的研究。在美国博士后工作期间,从事不锈钢在水环境、循环加载、高温条件下的疲劳机理,氢脆现象微观力学机理,氢在微裂纹附近的扩散,疲劳晶体塑性理论,高温效应,氧化腐蚀等研究;在哈尔滨工程大学主要从事基于多尺度-多场耦合方法的极端环境下金属/合金的疲劳特性研究。