砂轮约束磨粒喷射精密光整加工微观形貌及耐腐蚀特性研究

本文主要对磨粒喷射精密光整加工表面进行几何特性评价及耐腐蚀特性研究,通过对表面微观轮廓高度参数、横向间距特性参数以及微观形状特性参数研究表明,磨粒喷射加工表面微观高度特性参数Ra值、Rq可降低50%以上,同时,Rz、Ry、Rt、Rp和Rm也都大幅度下降,喷射加工表面轮廓高度特性参数值比磨削加工明显改善;喷射加工表面轮廓微观不平度的平均间距Sm和轮廓的单峰平均间距S都不同程度降低.轮廓微观不平度间距明显减小,轮廓对于中线的交叉密度增加.利用SHR20步入式恒定湿热淋雨结合试验箱,实验研究了表面形貌对抗腐蚀性能的影响,结果表明,和磨削加工相比,磨粒喷射加工表面耐腐蚀性能明显提高,在相同的腐蚀条件下,喷射光整加工表面腐蚀量最轻,磨削烧伤表面腐蚀量最大.

Investigation on microscopic morphology and erosion characteristics finished by abrasive jet with grinding wheel as restraint

The surface microscopic topography and corrosion resistance characteristics finished by abrasive jet with grinding wheel as restraint were evaluated and analyzed. The machined surface morphology was studied using SEM and microscope, and microcosmic geometry parameters were measured with TALYSURF5 instrument. The measurement results show that the profile longitudinal parameter values ,such as Ry ,Rq ,Ra and Rz of abrasive jet finishing surface diminished by 30% - 50% in comparison with ground surface, thus the surface roughness was improved. On the other hand, abrasive jet machined surface profile transverse parameter values, such as Sm and S were lower than grinding machined surface also. The waviness average spacing was decreased and ,ripple and peak density were increased for finishing surface compared to grinding machining. The corrosion resistance characteristics of finished surface were also investigated with damp-heat tester of SHR20. The experimental results show that the erosion amounts of finishing machined surface were obviously decreased compared with ground surface. Under the same experimental condition, the erosion amounts of ground burned were the biggest among all experiment specimens.