一种基于能量耗散的对接接头疲劳寿命快速预测模型  

A rapid fatigue life prediction model of butt joints based on energy dissipation

作　　者：魏巍[1,2,3] 孙杨[2,3] 赵兴明 陈明华 邹丽 杨鑫华[2,3] WEI Wei;SUN Yang;ZHAO Xingming;CHEN Minghua;ZOU Li;YANG Xinhua(Liaoning University of Technology,Jinzhou,121001,China;Dalian Jiaotong University,Dalian,116028,China;Liaoning Key Laboratory of Welding and Reliability of Rail Transportation Equipment,Dalian,116028,China)

机构地区：[1]辽宁工业大学,锦州121001 [2]大连交通大学,大连116028 [3]辽宁省轨道交通装备焊接与可靠性重点实验室,大连116028

出　　处：《焊接学报》2023年第8期91-97,I0008,共8页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51875072和52005071);辽宁省高等学校国境外留学项目(2018LNGXGJWPY-YB012);辽宁省自然科学基金项目资助项目(MS-2021-319);辽宁省教育厅基本科研项目青年项目(LJKQZ20222271);辽宁工业大学博士科研启动基金(XB2022001).

摘　　要：通过引入ISV(internal state variable)本构模型中的α和β变量,建立了一种与对接接头高周疲劳滞弹性和非弹性行为相关的能量耗散模型,并定义了两个特征应力幅,即标志着可恢复滞弹性和不可恢复非弹性行为开始形成的关键应力幅σ_(c0)和σc1(疲劳极限);借助该能量耗散模型,研究了不同应力幅下的对接接头能量耗散响应情况,发现能量耗散在疲劳极限附近呈现从线性响应到非线性响应的过渡;在此基础上,考虑到当应力幅高于疲劳极限时,全寿命周期的能量耗散存在临界值,结合与损伤相关的非弹性耗散,研发了一种基于损伤累积的疲劳寿命预测模型,并对接头的疲劳寿命进行了快速预测.结果表明,经预测数据和试验数据拟合的中值S-N曲线一致程度较好,从而证明了模型可用于实现对接接头的疲劳寿命快速、精确预测.An energy dissipation model for high cycle fatigue linked to anelastic and inelastic behavior of butt joints is developed by introducingαandβvariables of the internal state variable(ISV)constitutive model.The crucial stress amplitudes,σc0 andσc1(fatigue limit),corresponding to the onset of recoverable anelastic and unrecoverable inelastic behavior,are defined as two characteristic stress amplitudes.The energy dissipation response of butt joints under different stress amplitudes is examined using this energy dissipation model.The results demonstrate that when stress levels are close to the fatigue limit,the energy dissipation exhibits a transition from a linear response to a nonlinear response.On this basis,considering that when the stress amplitude is above the fatigue limit,there is a critical value for the energy dissipation during the fatigue duration,a fatigue life prediction model based on damage accumulation is developed in combination with the damage-related inelastic dissipation,thereby reaching a rapid fatigue life prediction.The results show that the median S-N curve fitted by the predicted data and the test data is in good agreement,and this validates that the proposed model can be utilized to realize a rapid and accurate prediction of the fatigue life of butt joints.

关 键 词：ISV模型 能量耗散 疲劳寿命 S-N曲线 

分 类 号：TG405[金属学及工艺—焊接]