冲击载荷作用下抽筒子疲劳寿命预测与试验验证

摘要

在火炮发射过程中，抽筒子在冲击载荷作用下，经常产生疲劳断裂。为了实现有针对性的预防性维修，提出了一种冲击载荷作用下基于协同仿真技术的不规则零部件疲劳寿命预测方法。基于 Pro/E 和ADAMS建立了火炮射击过程的虚拟样机，并从定性和定量两个方面进行验证，仿真得到抽筒过程中抽筒子的载荷谱。结合有限元分析，计算抽筒子在静应力下的强度和寿命。在仿真载荷谱和有限元静应力分析的基础上，结合材料的S N 曲线，建立了抽筒子疲劳损伤与寿命预测模型，得到其危险部位的最小寿命。为了验证疲劳寿命预测模型的有效性，设计了由撞击试验台、传感器和信号测试分析系统组成的抽筒子疲劳寿命验证试验装置，根据抽筒过程和仿真载荷谱，合理确定撞击高度。试验结果验证了所建立的疲劳寿命预测模型的可信性。%Fatigue fracture is the familiar failure mode of cartridge extractor under impact load in the process of gun firing.A new kind of fatigue life prediction method of irregular compo-nents under impact load was put forward based on collaborative simulation technology.Virtual prototype in process of gun firing was established by use of Pro/E and ADAMS.It was verified with the help of qualitative and quantitative methods.The load spectrum of the cartridge ex-tractor during extracting cartridge was acquired by means of virtual prototype simulation.The strength and life of the extractor under static stress were calculated based on finite element a-nalysis.On the basis of the load spectrum and finite element analysis results,fatigue damage and life prediction model of the extractor was established and minimum lives of hazardous loca-tion were calculated.To verify the validity of fatigue life prediction model,a kind of fatigue life verification test device was designed,it consists of impact test platform,sensor,signal test and analysis system.The impact height was specified according to the cartridge extracting process and the load spectrum provided by the virtual prototype.The test results verify the credibility of the established fatigue life prediction model.