SiCf/SiC复合材料铣磨表面质量评价方法试验研究

SiCf/SiC复合材料是典型的非均质、各向异性材料，金属材料质量评价体系已不完全适用，亟需建立适宜的表面质量评价方法。结合超声振动辅助铣磨试验，对比铣磨表面二维粗糙度Ra和三维粗糙度Sa测量数据的稳定性，探索Sa测量区域大小对测量结果的影响规律，并结合宏观、微观及三维形貌对试验结果进行分析研究。基于铣磨表面较为明显的、表现形式为凹坑的区域面积比例，开展表面质量情况分析研究。结果表明：Sa更适宜作为SiCf/SiC复合材料铣磨表面粗糙度特征参数，且最小测量区域大小为7mm×7mm；基于表面粗糙度分析，结合宏观、微观和三维形貌可进一步评价铣磨表面质量；采用表面明显凹坑面积比，基本可以实现对表面质量影响较大区域的定量分析。

Experimental investigation on evaluation method of milling-grinding surface quality for SiCf/SiC composite

Since SiCf/SiC composite is typical heterogeneous and anisotropic material, the metal material quality evaluation system is not fully appli-cable. There is an urgent need to establish a suitable surface quality evaluation method. Combined with the ultrasonic vibration-assisted milling-grinding test, comparing the stability of the 2D roughness Ra and 3D roughness Sa of the milling-grinding surface, and exploring the influence of the size of the Sa measurement area on the measurement results. Combined with the macroscopic, microscopic and 3D morphology, analyzing and studying the experimental results. Based on the area ratio of the more obvious areas with the appearance of pits on the milling-grinding surface, the analysis and research on the surface quality are carried out. The results show that Sa is more suit-able as the characteristic parameter of milling-grinding surface roughness of SiCf/SiC composites. And the Sa minimum measurement area size is 7mm×7mm. Based on roughness analysis, the milling-grinding surface quality can be further evaluated by combining macro-scopic, microscopic and 3D topography. Using the area ratio of obvious pits on the surface, the quantitative analysis of the area that has a great influence on the surface quality is basically realized.