高功率激光辐照CFRP的温度场和应力场的数值分析

为了研究高功率激光致碳纤维/环氧树脂复合材料的热损伤规律，采用COMSOL软件对多层结构的碳纤维/环氧树脂复合材料的热应力进行模拟计算，取得了不同功率密度激光辐照复合材料的瞬态温度场与应力场的时空分布及变化规律。测量得到不同功率密度的激光作用碳纤维/环氧树脂后的损伤面积和损伤形貌，与数值模拟结果的趋势吻合。结果表明，靶材表面辐照中心点温度在872K时出现温度平台，即相变潜热期与逆相变潜热期，并随着激光功率密度变化；激光辐照靶材对上表面碳纤维产生了极大的轴向压应力，功率密度为293W/cm2时，压应力差值约为1.87MPa；功率密度为3453W/cm2时, 压应力差值约为1.42MPa。这一结果对高功率激光致碳纤维/环氧树脂复合材料的热损伤研究提供了理论基础。

Study on numerical analysis of temperature field and stress field of carbon fiber reinforced polymers irradiated by high power laser

In order to study the thermal damage law of carbon fiber reinforced epoxy composite induced by high power laser, the thermal stress of carbon fiber reinforced epoxy composite with multilayer structure was simulated by COMSOL software. Theoretical analysis and experimental verification were carried out. The temporal and spatial distribution and change of the transient temperature field and stress field of composite materials irradiated by laser with different power densities were obtained. The damage area and morphology of carbon fiber/epoxy resin treated with different laser power density were measured, which was consistent with the trend of numerical simulation results. The results show that, when the temperature of the irradiation center of the target surface is 872K, a temperature plateau appears, that is, the latent heat period of phase change and the latent heat period of reverse phase change, and changes with the laser power density. The laser irradiation target material produced a great axial compressive stress on the upper surface of the carbon fiber. When power density is 293W/cm2, the compressive stress difference is about 1.87MPa; when power density is 3453W/cm2, the compressive stress difference is about 1.42MPa. This result provides a theoretical basis for the research on the thermal damage of carbon fiber/epoxy resin composites caused by highpower lasers.