循环载荷下HTPB推进剂温度演化及疲劳性能预测

摘要

The fatigue properties of hydroxyl terminated polybutadiene(HTPB) propellant specimen at room temperature were studied by using infrared thermography.Based on the assumption of the limiting energy theory,a energy model of Miner's linear cumulative damage theory was established to predict the residual life of materials.The temperature change during fatigue loading was explained by a theoretical model based on heat conduction,thermoelasic and inelastic effects.Results show that the temperature evolution in the fatigue loading process of HTPB propellant is mainly divided into three stages:initial temperature rise,temperature stabilization and temperature rise rapidly.The fatigue limit of HTPB propellant predicted by infrared thermography is 0.102 MPa and 0.113 MPa,the relative errors are 3.55％ and 14.7％ compared with the experimental result of 0.0985 MPa.The S-N curve obtained by the energy method is in good agreement with the S-N curve obtained by the traditional test method.Miner's energy model can accurately predict the residual life of the HTPB propellant under cyclic loading,and the relative error with the actual life is not more than 10％.%通过红外热像法研究了端羟基聚丁二烯(HTPB)推进剂试件室温下的疲劳性能,基于极限能理论假设,建立了Miner线性累积损伤理论的能量模型以预测材料的残余寿命.采用基于热传导、热弹性和非弹性效应的理论模型解释了疲劳加载过程中的温度变化.结果表明,HTPB推进剂疲劳加载过程中的温度变化分为初始温度上升、温度稳定和温度快速上升三个阶段.红外热像法预测的HTPB推进剂疲劳极限为0.102 MPa和0.113 MPa,与试验结果0.0985 MPa的相对误差为3.55％和14.7％.能量法得到的S-N曲线与传统试验法的S-N曲线吻合较好,Miner理论的能量模型能准确的预测循环载荷作用下HTPB推进剂的残余寿命,与实际寿命的误差不超过10％.