基于镀层界面剪切疲劳损伤的枪管寿命预测研究

Life Prediction of Gun Barrel Based on Shear Fatigue Damage of Coating Interface

为研究枪管内膛损伤机理、提高枪管寿命,提出了基于枪管镀层界面剪切疲劳损伤累积的枪管寿命预测方法。根据身管镀层剪切失效理论和疲劳损伤累积理论,建立了热压耦合应力作用下的枪管镀层界面剪切失效模型。以某5. 8 mm小口径步枪枪管为研究对象,计算一个冷却周期150发弹连续射击过程中的枪管界面剪切应力,结合随温度变化的枪管材料抗拉强度数据对枪管寿命进行了预测。研究结果表明:预测结果与寿命试验结果高度吻合,验证了寿命预测模型的可行性与正确性;以镀层界面剪切疲劳寿命来预测枪管寿命是有效的,镀层界面剪切疲劳失效是导致枪管寿终的重要原因。

According to the theories of coating shear failure mechanism and cumulative fatigue damage of gun barrel,a gun barrel life prediction method based on the shear fatigue damage accumulation at the interface of coating and substrate in barrel is proposed to study the bore damage mechanism of gun barrel and improve the gun barrel life. A shear failure model of coating interface under the effect of thermo-pressure coupling stress is built,and the shear stress of coating interface during continuous firing of 150 rounds is calculated by taking a 5. 8 mm caliber gun barrel as study object. The barrel life is predicted by use of temperature dependent tensile strength of gun barrel material. The predicted results match well with life test results,which verifies the feasibility and validity of the proposed life prediction model. The research results show that the prediction of gun barrel life based on the shear fatigue life of coating is feasible and the shear fatigue failure of coating interface is an important reason to lead to the life end of gun barrel.