Surface Integrities of Different Trajectories in Belt Grinding for Pure Iron Functional Performance Test Pieces

In order to reduce the influence of surface burns and other defects in the processing of pure iron parts for a functional properties test, and to improve the accuracy and usability of the test results, abrasive belt grinding is used for surface grinding. Because of the long circumference of the belt, and the long cooling time of the abrasive particles, cold grinding can be achieved, so that the incidence of surface burns, machining hardening, and other defects can be reduced. An experimental platform for belt grinding of pure iron parts for a functional properties test was built, and corresponding belt grinding experiments were carried out. The influences of grinding parameters, such as belt velocity, feed velocity, the grinding track on the microcosmic morphology, surface roughness, surface residual stress, and micro-hardness were studied. The results showed that belt grinding improved the surface integrity, the surface roughness was less than Ra 0.4 μm, the surface residual stress ranged from −253.84 MPa to −164.14 MPa, and the micro-hardness ranged from 118 HV to 170 HV. Furthermore, to get the workpiece surface to mostly suit the functional performance test, a high abrasive belt linear speed, a low grinding depth, and a feed speed should be selected, and the processing should be conducted with a circular trajectory.