掺杂相对ZrB_(2)陶瓷涂层抗激光烧蚀性能的影响

Effect of doping phase on laser ablation resistance of ZrB_(2)ceramic coatings

耐高温陶瓷作为高熔点材料,具有优异的高温抗烧蚀性能,有可能满足未来抗激光防护的需求。为摸清ZrB_(2)陶瓷涂层抗激光防护性能,采用高功率固体激光器作为测试光源,搭建了激光烧蚀实验平台和激光耦合特性测量系统,重点对ZrB_(2)陶瓷涂层开展了激光烧蚀实验和涂层反射率测试。实验研究了不同激光参数条件下ZrB_(2)涂层抗激光烧蚀性能,以及掺杂相(SiC、MoSi_(2))的影响。结果表明,相比于未掺杂ZrB_(2)涂层,掺杂后ZrB_(2)涂层抗激光烧蚀能力明显下降。分析认为掺杂相可提高ZrB_(2)涂层抗氧化性能,但不利于发挥氧化生成物ZrO_(2)的高反射和隔热作用,致使抗激光损伤阈值降低。激光损伤前后涂层反射率的测试结果,也证实了ZrO_(2)的高反射率是增强ZrB_(2)涂层抗激光损伤阈值的关键。同时,利用有限元软件建立了连续激光烧蚀下ZrB_(2)陶瓷涂层温度计算模型,并以基底发生熔化为判据,仿真得到了陶瓷涂层典型的抗激光烧蚀阈值参数。

High temperature resistant ceramics,as high melting point materials,have excellent hightemperature ablation resistance and may meet the needs of future laser protection.In order to understand the laser protection performance of ZrB_(2)ceramic coating,a high-power solid-state laser was used as the test light source,and a laser ablation experimental platform as well as laser coupling characteristic measurement system were established.The focus was on conducting laser ablation experiments and coating reflectivity tests on ZrB_(2)ceramic coating.The laser ablation resistance of ZrB_(2)coatings under different laser parameter conditions,and the influences of doped phases(SiC,MoSi_(2))were studied by experiment.The results show that compared to the undoped ZrB_(2)coating,the doped ZrB_(2)coating shows a significant decrease in laser ablation resistance.The conclusion analysis suggests that the doped phase can improve the oxidation resistance of ZrB_(2)coating,but it is not conducive to the high reflection and insulation effects of the oxidation product ZrO_(2),resulting in a decrease in the threshold of laser damage resistance.The reflectivity test results of the coating before and after laser damage also confirms that the high reflectivity of ZrO_(2) is the key to enhancing the laser damage resistance threshold of ZrB_(2)coating.Meanwhile,a temperature calculation model for ZrB_(2)ceramic coating under continuous laser ablation was established by using finite element software,and the typical laser ablation threshold parameters of ceramic coatings were simulated based on the criterion of substrate melting.