纳秒激光单脉冲对阻尼橡胶材料的损伤特性

Damage Properties of Single Pulse of Nanosecond Laser on Damping Rubber Material

为了研究阻尼橡胶材料与纳秒激光的相互作用,通过单脉冲激光进行刻蚀实验,观察了橡胶材料的损伤情况,分析了其损伤机理。结果表明,短脉冲激光能量作用于阻尼橡胶材料表面时,由于橡胶材料的热传导系数较低,激光能量所产生的热量将极大地集中在光斑区域内。在高温条件下,橡胶材料发生热裂解、老化等现象,所形成的孔洞内呈现出明显的蜂窝状的热烧蚀状态。随着单脉冲能量的增加,孔的深度和直径增大,且孔内的烧蚀状态更加明显。通过测量烧蚀直径和深度,计算了阻尼橡胶材料在13ns激光单脉冲作用下的损伤阈值。利用有限元方法模拟了阻尼橡胶材料的单脉冲损伤过程,利用模拟结果再次计算了材料的单脉冲损伤阈值,与实验结果吻合较好。

To study the interactions of single nanosecond laser pulses with damping rubber materials, etch experiment is carried out by single pulsed laser. Damage situation of the material is observed and damage mechanism is analyzed. The results show that the heat generated by the laser energy is mostly focused on the spot area due to the low heat transfer coefficient of the damping rubber material, while short pulsed laser energy affects on the surface of damping rubber material. As a result, thermal cracking and ageing of the rubber are apparent and a thermal ablation like honeycomb in the holes are shown under the condition of high temperature. The diameter and the depth of the holes are increased with the increasing of the single pulse energy and the ablation state of the rubber in the holes is more significant. The damage threshold of the 13 ns single laser pulse on the damping rubber material is calculated by measuring the ablation diameter and depth. The damaging process of the damping rubber material by a single laser pulse is simulated by the finite element method, and single pulse damage threshold of the material is calculated again with the simulation results. The result shows good agreement with the experiment result.