Research on simulation and experiment for surface topography machined by a novel point grinding wheel

Abstract

Grains motion path will be changed in the point grinding process due to the existence of variable angle α. To verify the difference between point grinding and traditional grinding, the moving relationship and coordinate transformation between grinding wheel and workpiece are used to put the grain movement function equivalent to parabola, then point grinding cutting path is concluded. Based on grains distribution on the grinding wheel surface, the 3D geometry simulation topography of workpiece is obtained by extending the effective interference trails along the axial direction. Furthermore, a vitrified bond CBN wheel with a coarse grinding area angle θ is proposed and the principle of design and preparation of these novel grinding wheels are studied. The typical processing parameters are chosen to grind QT700 ladder shaft; the simulation results are verified by using the VHX-1000E microscope and the non-contact 3D surface profilometer to observe the workpiece surface topography and measure the surface roughness. The results indicated that the simulation microstructures coincide well with the experimental measurements and the values of simulation roughness are 0.5 times of experiments. So, the geometric simulation model provided an auxiliary and prediction method for the actual processing topography analysis. In addition, grinding wheels with different θ are used to grind ladder shafts with a series of grinding parameters. The influence trend of inclining angle α, cutting depth a_p, axial feeding speed v _f and grinding wheel speed v _s on surface roughness is obtained. It is concluded that the values of workpiece surface roughness using novel grinding wheel are less than using the traditional grinding wheel under the condition of the same processing parameters.