关键词: 创成机理, 精密光整加工, 磨粒喷射, 三维形貌, 自相关函数

Abstract: The aim of abrasive jet flow finishing process as a new lapping techonology is to remove further the surface defect layer and diminish roughness and ripple. Experiments are performed on a cylindrical grinder MB1332A with a 45 steel workpiece as specimen of which the surface roughness values is 0.6 μm. The micromorphology of machined surface morphology is observed by using scanning electron microscope and the microcosmic geometry parameters are measured with Micromesvre2 profilometer. With ACF the surface during grinding and further lapping with liquid abrasive jet flow are researched. The material removal mechanism and the mechanism of surface morphology finished by the novel process is investigated. The energized free abrasives polish, wipe off and micro-cut the workpiece surface in wedge-like zone which is the main factor in material removal and the lateral extrusion of abrasive fluid is the main factor of homogenizing and lowering ripples. The result indicates that the machined surface changes from continuous parallel micro-groove to randomly distributed discontinuous micro-pit and the surface roughness values gradually decreases from an initial value of about 0.6 μm down to about 0.2 μm with the increase of machining cycles. Furthermore, the isotropy surface and uniformity veins both parallel and perpendicular machining direction are attained by the finishing process to improve greatly the wear resistance of the workpiece.

Key words: 3D profile, Abrasive jet, Auto correlation function(ACF), Generating mechanism, Precision finishing