激光辐照下固体材料的温度分布理论研究

 考虑到有限厚介质的表面热对流，利用格林函数方法理论计算了强激光作用下介质材料的3维温度分布，给出了温升与材料尺寸的关系式及其关系曲线。以单晶硅材料为例进行了模拟计算，结果表明：温升不仅与材料本身的性质（热容，热导率，密度）密切相关，而且还与材料的吸收系数，激光加热参数（功率密度，能量分布，光斑大小，作用时间），以及对流换热系数有关。在激光照射的初始阶段，材料表面温度迅速增加；其后，随着激光照射时间的增加，温度增加量逐步变缓。

Theoretical analyses of temperature distributions of solid materials irradiated by high power laser

For finite-thickness media with convective surface losses, the three-dimensional temperature distributions of solid materials which are due to absorption of laser light with a Gaussian power-density profile, are calculated using the well-known Green's function methods. Some expressions and theoretical profiles of the temperature distributions as functions of the size and the thickness of a substrate are obtained. The results of the calculations show that the temperature rise is closely related to the nature of the medium itself (specific heat, thermal conductivity, density), as well as to the absorption coefficient of medium, the parameters of the incident laser (power density, energy distribution, spot size, irradiating time), and the convective heat-transfer coefficient. The temperature rise of the medium surfaces increases quickly at the beginning of laser heating, and then it becomes insensitive to laser heating and increases slowly with time.