随机振动下镍钛形状记忆合金管接头的疲劳寿命分析

针对管路系统中Ni-Ti合金管接头随机振动问题进行了随机振动疲劳寿命分析.以某飞机典型液压管路中的Ni-Ti合金管接头为研究对象,采用基于高斯分布和Mine线性累计损伤定律的Steinberg法,得到了疲劳损伤的计算公式.基于描述Ni-Ti形状记忆合金超弹性和记忆效应的本构模型,建立了管接头有限元模型,进行模态分析和随机振动响应分析,并利用疲劳损伤的计算公式预测结构的疲劳寿命.结果表明:Ni-Ti形状记忆合金管接头在80 000 h的飞行寿命内是安全可靠的,为管接头的设计和优化提供了理论参考.

Fatigue life analysis of Ni-Ti shape memory alloy pipe joints under random vibration

Random vibration fatigue life analysis of Ni-Ti alloy pipe joints in pipeline system was carried out. Taking Ni-Ti alloy pipe joints in a typical hydraulic pipeline of an aircraft as a research object, the formula for evaluating overall fatigue damage in the joints is obtained by using the Steinberg method based on Gauss distribution and Mine linear cumulative damage law. Based on the constitutive model describing thehyperelasticity and memory effect of Ni-Ti shape memory alloy,the finite element model of the pipe joint is established and themodal analysis and random vibration response analysis of the system model are then carried out, and the fatigue life of joint structures is predicted by using the fatigue damage formula. Predicted results show that the Ni-Ti shape memory alloy pipe joints are safe and reliable within the flight life of 80 000 h, which may provide a theoretical reference for design and optimization of the pipe joints.