摘要
针对传统S-N曲线所需试验周期长、样本数量大等特点,陈述了一种将焊接接头高周疲劳寿命、疲劳极限及统计学结合起来的三参数S-N曲线快速预测模型。通过确定随载荷增加的稳定温升阶段能量耗散转折点,并以此为索引进行疲劳极限预测。考虑当载荷高于疲劳极限时,试件全寿命周期内的累积损伤阀值存在,建立基于能量耗散阀值的中值S-N曲线预测模型。然后,结合极大似然法完成存活率为95%的S-N曲线快速预测。为验证模型的有效性,将预测S-N曲线与试验数据进行对比,结果表明试验数据基本分布在中值S-N曲线和存活率为95%的S-N曲线之间,从而验证了模型的精确性。
In view of the characteristics of the traditional S-N curve requiring long test period and large number of samples,a three-parameter S-N curve rapid prediction model combined with the high cycle fatigue life,fatigue limit and statistics of welded joints was presented.Through determining the turning point of energy dissipation in stable temperature rise stage under gradually increasing of load,and this turning point was then regarded as an index for predicting the fatigue limit.Considering the cumulative damage threshold in the whole lifespan when the load was above the fatigue limit,a median S-N curve prediction model based on the energy dissipation threshold was established.Then,combined with the maximum likelihood method,the S-N curve prediction with the survival probability of 95%was completed.To verify the validity of the proposed model,the predicted S-N curve was compared with the experimental data.Results showed that the experimental data were basically distributed between the median S-N curve and the S-N curve with 95%survival probability,which verified the accuracy of the model.
作者
魏巍
邹丽
杨鑫华
Wei Wei;Zou Li;Yang Xinhua(Dalian Jiaotong University,Dalian 116028,Liaoning,China;Liaoning Key Laboratory of Welding and Reliability of Rail Transportation Equipment,Dalian 116028,Liaoning,China)
出处
《焊接》
北大核心
2021年第4期13-18,62,63,共8页
Welding & Joining
基金
国家自然科学基金资助项目(51875072,52005071)
辽宁省高等学校国(境)外培养项目(2018LNGXGJWPY-YB012)。
