旋轮进给率对小锥角锥形件表面形貌及显微组织的影响

目的通过旋压工艺试验,考察旋轮进给率对锥形件表面质量的影响,探讨表面缺陷的形成机理。方法采用4个不同的旋轮进给率分别进行旋压试验,在扫描电镜下观察其表面形貌及腐蚀后的显微组织,分析其表面形貌变化规律、晶粒尺寸分布情况,并与初始表面形貌及显微组织进行对比分析。结果进给率越大,表面波纹越明显,板坯表层金属被旋轮剥离越严重且晶粒大小分布越不均匀;进给率较小时,锥形件表面光滑,且晶粒大小分布均匀。结论进给率对表面造成缺陷的形成机理是表层金属被剥离,表面波纹是导致晶粒大小分布不均匀的原因。

Influences of Spinning Roller Feed Rate on Surface Morphology and Microstructure of Conical Parts with Small Angle

The paper aims to investigate the influences of spinning roller feed rate on surface quality of conical parts by spinning process test, and to explore the formation mechanism of surface defects. Four different spinning roller feed rates were used for spinning test; and the surface morphology and microstructure after corrosion were observed under scanning electron microscopy; the variation of surface morphology and the grain size distribution were analyzed and compared with the initial surface morphology and microstructure. The results show that when the feed rate was large, the surface ripples were more obvious, the surface metal was more severely scraped by the roller, and the grain sizes were more uneven; and accordingly, the smaller the feed rate, the more smooth the cone surface, and the more even the grain sizes. The formation mechanism of the defect caused by the feed rate is that the surface metal is scraped off. The cause of uneven grain size distribution is the surface ripples.