【摘要】 研究了在多脉冲强激光辐照下靶材的热传导与热冲击特性。基于非傅里叶导热定律和热弹性理论,推导出多脉冲激光辐照下靶材温度场和热应力场的解析式;结合适当的边界条件,以不锈钢靶材为例,利用有限差分法和Matlab计算得到了多脉冲强激光辐照下靶材内部过余温度随时间和深度演化情况以及内部热应力的演化规律。计算结果表明:多脉冲激光辐照下靶材热响应在离边界不同截面处温度波形变化出现延迟性,其滞后性能与弛豫时间有关;非傅里叶解中应力波的波前十分陡峭,具有明显的热冲击性。更多还原

【Abstract】 The effect of the thermal shock and thermal conduction of target irradiated by multi-pulse laser is studied. Based on the non-Fourier law and thermo-elastic theory,the non-Fourier expressions of the temperature field and the thermal stress field of target under multi-pulse laser irradiation were deduced. Taken stainless steel target as an example,thermal conduction and thermal stress equations under an appropriate boundary condition were solved by using the finite difference method. The temperature distribution and thermal stress distribution were obtained as function of time,relaxation time and location. The results show that the effect of thermal conduction of target irradiated multi-pulsed laser presents the temperature waves and the variety of temperature waves is postponed by the relaxation time. It is also found that the target has the stress waves with obvious thermal shock in the non-Fourier solutions.更多还原