MoSi_(2)-YSZ高发射涂层对硅橡胶基防热材料的隔热及抗热振性能影响

Effect of the MoSi_(2)-YSZ High-emissivity Coatings on the Performance of Thermal Insulation and Thermal Shock Resistance of Ablative Materials Based on Silicone Rubber

制备了MoSi_(2)-YSZ复合硅橡胶基辐射型热防护涂层,并对其耐烧蚀性能和抗热振性能进行了表征。结果表明:与传统烧蚀型涂层相比,辐射型涂层在0.3~2.5μm波段发射率达到0.93以上,且静态热流测试背板温升降低60%,热振测试背板温升降低30%。辐射型涂层在热振测试中由于辐射散热机制表现出对温度响应的迟滞性,使得背板温度变化率的峰值降低40%。MoSi_(2)氧化形成的致密氧化层具有良好的保护性和自愈合性,从而提高了涂层的耐烧蚀和抗热振性能。

Silicone rubber-based radiant thermal protection coating was prepared by MoSi_(2)-YSZ filler and characterized with ablation resistance and thermal shock resistance.Compared with traditional ablation coating,the high-emissivity coating with MoSi_(2)-YSZ has an emissivity over 0.93 in the range of 0.3~2.5μm,the temperature rise of the backboard of high-emissivity coating is reduced by 60%in static heating condition,while the temperature rise of the thermal shock test is reduced by 30%.High-emissivity coatings exhibit hysteresis in response to temperature due to the heat dissipation of radiation during high temperature testing,the peak temperature change rate of the backboard is reduced by 40%.In addition,the dense oxide layer formed by MoSi_(2)oxidation also has good protection and self-healing properties for the inner structure,which greatly increases the stability and reliability of the coating under high temperature conditions.