一种基于耗散能计算的高周疲劳参数预测方法  

A PREDICTION METHOD ON HIGH-CYCLE FATIGUE PARAMETERS BASED ON DISSIPATED ENERGY COMPUTATION

作　　者：李源[1,2] 韩旭[1] 刘杰[1] 姜潮[1] 

机构地区：[1]汽车车身先进设计制造国家重点实验室,湖南大学机械与运载工程学院,长沙410082 [2]国防科学技术大学指挥军官基础教育学院,交通运输工程系,长沙410073

出　　处：《力学学报》2013年第3期367-374,共8页Chinese Journal of Theoretical and Applied Mechanics

基　　金：国家自然科学基金(51175160);装备预先研究(62501036012);国防科技大学预先研究(JC11-09-01)资助项目;国家留学基金委(CSC)的访问学者资助~~

摘　　要：在热力学框架下,基于薄板假设,建立金属材料薄板试样在高周疲劳载荷作用下的热传导方程,将试样温度场数据和实时载荷信号导入,准确计算与高周疲劳损伤相关的单个循环内耗散能.基于该方法,以316L不锈钢材料为例,通过实时监测试样不同应力水平下高周疲劳破坏全过程中耗散能的变化,拟合出耗散能--疲劳寿命曲线,呈现与传统的应力--疲劳寿命曲线相同的规律;提出一种新的预测高周疲劳极限的能量法,确定的疲劳极限与实验值相近.A heat conduction equation under high-cycle fatigue loadings was established using sheet assumption within thermodynamic framework. Dissipated energy per cycle, correlated with fatigue damage, could be deduced from tempera- ture field data of specimen and real-time load signal. Then, taking 316L stainless steel for example, the dissipation energy per cycle variations were in-situ monitored during each high-cycle fatigue test under different stress levels. Dissipated energy versus fatigue lifetime curve shows the same pattern as the traditional stress versus fatigue lifetime curve. A new energy method was developed to predict high-cycle fatigue limit. The high-cycle fatigue limit determined by dissipated energy measurement was close to the experimental fatigue limit.

关 键 词：高周疲劳 金属材料 耗散能 疲劳寿命 疲劳极限 

分 类 号：O346.2[理学—固体力学]