TC4钛合金的多轴高周疲劳损伤及强度退化研究  

Multiaxial High Cycle Fatigue Damage and Strength Degradation of TC4 Titanium Alloy

作　　者：李炳强 吴超 李晨昀 周宏根[1] 刘金锋[1] Li Bingqiang;Wu Chao;Li Chenyun;Zhou Honggen;Liu Jinfeng(School of Mechanical Engineering,Jiangsu University of Science and Technology,Zhenjiang 212003,China)

机构地区：[1]江苏科技大学机械工程学院,江苏镇江212003

出　　处：《稀有金属材料与工程》2023年第5期1896-1904,共9页Rare Metal Materials and Engineering

基　　金：国防装备预研快速扶持项目(80902010701);国家重点研发计划专项(2020YFB1712600,2020YFB1712602);国家自然科学基金(51605204)。

摘　　要：不同工况下TC4(Ti-6Al-4V)钛合金疲劳累积损伤及强度退化存在较大差别。为了充分表征载荷参数的影响,基于Chaboche损伤模型以及改进的多轴疲劳损伤准则,提出新的强度退化模型,开展了TC4钛合金的多轴高周疲劳(HCF)寿命预测和强度退化评估。首先,开展TC4合金在一系列加载路径下的多轴比例和非比例疲劳试验。将Chaboche非线性损伤准则和临界平面法与提出的损伤控制参数相结合,描述了TC4合金的非线性疲劳损伤计算和寿命预测。其次,进一步建立了基于累积损伤的非线性强度退化模型,并证明了该模型在不同载荷工况下均可以获得更高的精度。实验结果表明,由于考虑载荷参数的影响,提出的TC4钛合金疲劳寿命与强度退化预测结果精度远高于其他的预测模型。There are great differences in fatigue cumulative damage and strength degradation of TC4(Ti-6Al-4V)titanium alloy under different working conditions.In order to fully characterize the influence of load parameters,based on Chaboche damage model and improved multiaxial fatigue damage criterion,a new strength degradation model was proposed to predict the multiaxial high cycle fatigue(HCF)life and to evaluate the strength degradation of TC4 titanium alloy.Firstly,the proportional and non-proportional multiaxial fatigue experiments of TC4 titanium alloy through five kinds of loading paths were carried out.The nonlinear multiaxial fatigue damage computation and life prediction of TC4 titanium alloy were conducted via union of the critical plane method and Chaboche damage criterion with the improved damage control parameters.Secondly,a cumulative damage based modified strength degradation model was further established,and it is proved that higher accuracy can be obtained using the model under different load conditions.The experimental results show that considering the influence of load parameters,the prediction accuracy of fatigue life and strength degradation of TC4 titanium alloy proposed in this research is much higher than that of other prediction models.

关 键 词：疲劳寿命 多轴损伤 强度退化 TC4钛合金 

分 类 号：TG146.23[一般工业技术—材料科学与工程]