基本信息
项目批准号：11602038
申请代码：A0812
项目名称：超長(cháng)寿命區(qū)间高强铝合金搅拌摩擦焊接头颗粒物(wù)致裂机理(lǐ)研究及寿命预测
项目负责人：何超
依托单位：成都大學(xué)
研究期限：2017-01-01 至 2019-12-31
资助经费：22.0（万元）

项目摘要
中文(wén)摘要：
高强铝合金搅拌摩擦焊（FSW）接头在汽車(chē)、航空航天、高速列車(chē)等领域有(yǒu)着广泛应用(yòng)，服役期间需承受循环载荷的長(cháng)期作用(yòng)，但目前其超長(cháng)寿命疲劳强度及失效机制尚未完全明确。本项目拟对高强度铝合金FSW接头的超長(cháng)寿命疲劳行為(wèi)进行试验研究，重点解决三个科(kē)學(xué)问题：（1）颗粒物(wù)在接头焊核區(qū)与热机影响區(qū)的存在形式及其导致疲劳裂纹萌生和扩展的机理(lǐ)；（2）FSW接头局部超長(cháng)寿命疲劳强度及失效机制；（3）FSW接头超長(cháng)寿命的预测方法。通过本项目的研究，可(kě)望阐明颗粒物(wù)对高强铝合金FSW接头超長(cháng)寿命疲劳失效的作用(yòng)机理(lǐ)，并提出有(yǒu)效预测接头超長(cháng)寿命疲劳强度的方法，对搅拌摩擦焊工艺制定、可(kě)靠性设计和寿命评估有(yǒu)着重要的科(kē)學(xué)意义和应用(yòng)价值。
英文(wén)摘要：
Friction stir welded (FSW) joints in high strength aluminum alloys have a widely application in automotive, aerospace, high speed railway and so on. In their working service, cyclic loading will be applied for a long time, but the super-long life fatigue strength and failure mechanisms are not clear. This project aims to experimentally investigate the Ultra-long life fatigue (ULF) behaviors of FSW joint in high strength aluminum alloys by focusing on three scientific problems: (1) distribution characteristics of particles in different subzones of welded joint and their effects on the fatigue crack initiation and propagation mechanisms; (2) local fatigue strength and failure mechanisms of FSW joints in ULF region; (3) prediction of fatigue life of FSW joints in ULF range. Based on the studies in this project, the effect of particles on ULF failure mechanisms of FSW joints would be clarified hopefully, and the prediction method for ULF strength would be proposed. Therefore, the project research has important theoretical and practical values for FSW process optimization, reliability design and life assessment.
 
                                                                                                                                                                              ——来自https://kd.nsfc.gov.cn/