复合材料表面双向反射分布函数实验研究

Experimental study of bidirectional reflectance distributi on function on surfaces of several composites

为研究泡沫铝、铝基石墨纤维、镁基石墨纤维和碳纤维铝等特种复合材料的表面红外辐射及散射特性,测量了其表面双向反射分布函数(BRDF)值.利用自行研制的双向反射分布函数(BRDF)测试台,分别在0.6328、1.34、3.39μm波段下,测量了上述材料在不同入射角下的表面双向反射分布函数值.实验结果表明:各种复合材料表面在可见光(0.6328μm)波段的BRDF值分布在0.3区域内,且多呈镜反射状态;而在近中红外(1.34μm和3.39μm)波段的BRDF值分布在0.08区域内,呈现出一定的漫反射特征,且分布强度比可见光波段低很多,反映出各表面对各波段的吸收率不同.

We measured the bidirectional reflectance distribution function of special composites such as foamed aluminum, aluminum-based graphite fiber, magnesium-based graphite fiber and carbon fiber （ aluminum）, to study their infrared radiation and scattering characteristics. Using the self-development Bidirectional Reflec- tance Distribution Function experimental device, we measured their infrared bidirectional reflectance distribution function （BRDF） in 0. 6328 μm,1.34 μm and 3.39 μm band at different incidence angles. The experimental results show that the BRDF changes in the region of 0. 3 in visible light （0. 6328 μm） and shows specular reflection features; while in infrared light （ 1.34 μm and 3.39 μm） band, the BRDF changes around 0. 08, and shows diffuse reflection features to some extent, and the light intensity is much weaker than that of visible light, which means the composites have different surface absorptivity on different bands.