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We propose a novel point grinding wheel (NPGW) with coarse grinding zone angle θ. According to earlier studies, this type of grinding wheel has high grinding efficiency, long service life, and generates very little surface roughness. The contact zone between the grinding wheel and workpiece is modified by the addition of the NPGW with the coarse grinding zone angle θ and the inclined angle α of point grinding process, and as a result, grinding force and grinding zone temperature are also altered. The grinding force theoretical model of NPGW was established and the grinding zone temperature was simulated by the finite element method, based on the theory of grinding heat generation and distribution and triangular heat source distribution model. At the same time, seven pieces of NPGW with different angles θ used for grinding experiments were fabricated. The theoretical model of grinding force and the simulation of grinding temperature coincided with experimental results. Therefore, the grinding force theoretical model and the grinding temperature simulation provide an auxiliary and predictive method for the actual process. Moreover, the influence of parameters on grinding force and grinding zone temperature can be obtained, and the results indicate that the NPGW and point grinding process can reduce grinding force and grinding zone temperature. Finally, plastic deformation is attributed to the production of compressive stress and grinding heat is attributed to the production of tensile stress. Therefore, the residual stress is influenced by the grinding force and the grinding temperature coupled. The residual stress of workpiece surface and subsurface was studied. In conclusion, the NPGW and point grinding process can reduce residual stress of workpiece surface and subsurface, in the case of tensile and compressive stress.

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 ap, axial feeding speed vf and grinding wheel speed vs 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.