基于能量耗散理论的载荷频率对A7N01铝合金高周疲劳行为影响  

Effect of load frequency on high cycle fatigue performance of A7N01 aluminium alloy based on energy dissipation theory

作　　者：程永明 方喜风 韩文峰 

机构地区：[1]中车青岛四方机车车辆股份有限公司,青岛266111

出　　处：《焊接学报》2017年第12期81-84,共4页Transactions of The China Welding Institution

基　　金：十二五国家科技支撑计划资助项目(2013BAG24B02)

摘　　要：文中基于能量耗散理论,针对A7N01母材及焊接试件分析载荷频率对材料疲劳寿命的影响.理论上进行推导得到试件疲劳寿命与循环加载初始阶段单位加载周期内的疲劳试件温度上升速率有关,通过设计10 Hz及128 Hz下的疲劳试验并测得不同频率下的温度演化曲线,可知频率对A7N01母材及焊接试件单位时间内的温升速率影响较大,但对单位循环加载周期内试件的温度上升速率影响很小,对该材料疲劳寿命的影响也不显著;此外还发现温度演化曲线在最初的几个循环内会有小幅度下降,这与试件的初始状态有关,该现象在低频加载时比高频加载时更加明显.The effect of load frequency on fatigue performance of A7 N01-T4 aluminum alloy base metal and welded jointwas investigated based on energy dissipation theory. The relationship between fatigue life and temperature rise rate of fatigue specimen in single load cycle during initial stage of cyclic loading was deduced theoretically. The temperature evolution curve of fatigue specimen with load frequency of 10 Hz and 128 Hz was tested. It was found that the load frequency had large influence on temperature climbing rate for A7 N01-T4 aluminium alloy base metal and welded joint in unit time,but had little influence on that in single load cycle and little effect on fatigue life. It was also noticed that the temperature evolution curve slightly dropped in initial several cycles and it was related to initial state of specimen. This phenomenon was more remarkable with low load frequency than with high load frequency.

关 键 词：A7N01-T4铝合金 高周疲劳 载荷频率 

分 类 号：TG431[金属学及工艺—焊接]