耐高温红外低发射率多层涂层设计及综合性能研究

发布时间：2018-04-03 05:33

  本文选题：共掺杂　切入点：电导率　出处：《南京航空航天大学》2017年硕士论文

【摘要】：现阶段对于耐高温低发射率涂层的应用,主要是针对于发动机及相关热端部件,可有效的降低其表面的红外辐射,起到保护作用。前一阶段课题组相关研究中,主要是以氧化铈基的耐高温低发射率涂层为主,其中,涂层单一的发射率或者抗热震性能都比较良好,但不能同时满足低红外发射率及高抗热震性能。为此,本文将以多层涂层结构模式来实现低发射率和高抗热震的兼容,从而提高涂层的综合性能,同时,研究并优化了涂层制备工艺参数,探究了提高涂层的发射率及抗热震性能等的相关方法。研究成果如下:1.利用共沉淀法,以Y~(3+)及Ca~(2+)共掺杂CeO_2可以明显降低其红外发射率,当Y~(3+)的掺杂量为15%且Ca~(2+)的掺杂量为5%时的粉体Ce_(0.8)Y_(0.15)Ca_(0.05)O_2-δ的发射率值最小为0.241,主要通过掺杂Y~(3+)及Ca~(2+)后提高其电导率从而降低其发射率。同时,利用辐照剂量为50KGy的60Coγ射线辐照处理粉体Ce_(0.8)Y_(0.15)Ca_(0.05)O_2-δ,其发射率在测试温度700°C时达到最低为0.147。以上述化学及物理改性后的粉体作为填料制备表层涂层,其发射率在600°C时到最低为0.282。2.通过La~(3+)及Mg~(2+)共掺杂CeO_2可以提高其热膨胀系数,以掺杂后的粉体为填料制备涂层即减少结合层与基板间的热膨胀系数差,从而提高了涂层的抗热震性能。3.通过正交实验研究了涂层喷涂的工艺参数最优配合方案,优化工艺参数涂料粘度、喷涂气压及喷枪倾斜角,从而减少涂层制备工艺对涂层性能的影响。4.按照设计的表层、结合层及过渡层的多层结构制备了CYC/CLM基多层涂层,测试了其综合性能,最低发射率值为0.284,抗热震达51次,并且其耐热及抗高温氧化等性能良好。
[Abstract]:At this stage for high temperature resistance and low emissivity coating applications, mainly for the engine and related hot end components, can reduce the infrared radiation of the surface effectively, play a protective role. Previous studies research group, is mainly based on ceria based high temperature resistance and low emissivity coating, wherein the emissivity of coating single or thermal shock performance is relatively good, but can not meet the low infrared emissivity and high thermal shock resistance. Therefore, this paper will take the multi-layer coating structure model to achieve low emissivity and high thermal shock compatibility, so as to improve the overall performance, high coating at the same time, research and optimization of the coating the preparation process parameters, to explore the related methods to improve the emissivity of the coating and thermal shock resistance. The research results are as follows: 1. using co precipitation method with Y~ (3+) and Ca~ (2+) Co doped CeO_2 can significantly reduce the infrared emissivity, when Y~ ( 3+)鐨勬幒鏉傞噺涓，

本文编号：1703873