利用研制的双光路对比法发射率测量装置对影响钢Q235 表面光谱发射率的几个因素分别进行了研究, 在823～1273 K 之间测量了几种粗糙度不同的钢样品表面光谱发射率；探讨了表面粗糙度对钢表面光谱发射率的影响；用非线性最小二乘法给出了发射率随温度的变化关系。研究结果表明：对于同种材料的钢Q235, 表面粗糙度对光谱发射率的影响在低温时比高温时更显著；钢表面光谱发射率随温度的升高呈指数关系增大, 升至1230 K 后, 钢表面光谱发射率趋于稳定；加热时间对光谱发射率的影响很小。

Several factors affecting the normal spectral emissivity of steel Q235 are investigated between 823 K and 1273 K by using double-light-path contrast measurement equipment and the spectral emissivity of different roughness is measured. The effect of roughness on spectral emissivity is studied and the relationship between the spectral emissivity and temperature is deduced by using the nonlinear least-square method. Experiment results shows that, the effect of surface roughness on spectral emissivity at low temperature is more remarkable than that at high temperature, the steel spectral emissivity increases with temperature according to exponential relation, however when sample temperature reaches 1230 K, the spectral emissivity is stable, and the effect of heating time on spectral emissivity can be ignored.