Analysis Of Chrome-Planted Barrel Mechanical Properties And Chromium Layer Crack Growth

To explore the factors affecting the life of the gun barrel,the mechanical behavior and variation characteristics of the chrome-plated barrel of a anti-aircraft gun under high temperature,high pressure and the temperature-pressure coupling were studied.The influence of rate of fire and barrel materials on the temperature and stress characteristics of the barrel and the extended characteristics of the cracks in the chromium layer of the barrel under the coupling of temperature and stress were investigated.The main contents are as follows.(1)Through the classical interior ballistic theory and the forced convection coefficient calculation method,the temperature,the pressure and relative boundary conditions of the chromium barrel were obtained.(2)The Heat transfer analysis model of chrome-plated barrel was established,and the temperature distribution characteristics and regularity of the key section of chrome barrel in single shot and continuous firing were analyzed,and the temperature distribution at the surface of chromium layer and steel chromium joint was studied.(3)Based on the thermo-solid coupling analysis model of chrome-plated barrel,the stress analysis of single shot and continuous firing temperature,pressure and temperature-pressure coupling was carried out on the key section of chrome-plated barrel,and the stress distribution law of chromium layer and steel chromium joint surface was studied emphatically.(4)The influence of the rate of fire and the material of the barrel on the temperature field and stress field of each key section of the barrel was studied.(5)The crack propagation process and crack tip stress characteristics of the barrel with initial crack defects under coupling stress were studied.