Secrets of high thermal emission of transition metal disilicides TMSi_(2)(TM=Ta,Mo)  

作　　者：Huimin Xiang Fuzhi Dai Yanchun Zhou 

机构地区：[1]Science and Technology on Advanced Functional Composite Laboratory,Aerospace Research Institute of Materials and Processing Technology,Beijing 100076,China

出　　处：《Journal of Materials Science & Technology》2021年第30期114-121,共8页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation of China under Grant Nos.51972089 and 51672064。

摘　　要：TMSi_(2)(TM=Ta,Mo)are extensively used as thermal emissivity agents in high emission coatings due to their well-known"high"emissivity in infrared range.However,there is a paucity of the high temperature(HT)emissivity property of these two silicides.Moreover,room temperature(RT)spectrometer measurements have demonstrated that the emittance in infrared range of two silicides was considerably low.Therefore,providing critical HT data and satisfactory elucidation on the emission incompatibility of TMSi_(2)is eagerly needed.In this contribution,combining first principles calculations and Drude model,the reflectance spectra of TMSi_(2)were predicted at both RT and HT.Consistent with spectrometer measurements,the intrinsic emittance of silicides was relatively low in the entire investigated temperatures.To explain the incompatible emission behavior,two simplified models including the majority of high emissivity coating,SiO_(2),were proposed.Intriguingly,with SiO_(2)considered in simulations,no matter covered on the surface or blended in the composites,the emittance of the TMSi_(2)enhanced significantly.Our theoretical results demonstrate the non-negligible significance of oxides on the high temperature performance of silicides and provide the guidelines for improving the emission performance of silicides and searching for potential high emissivity agents.

关 键 词：Disilicide Optical properties Thermal emission First-principles calculations Drude model 

分 类 号：TB34[一般工业技术—材料科学与工程]