Influence of Electroplated CBN Wheel Wear on Grinding Surface Morphology of Powder Metallurgy Superalloy FGH96.

The electroplated cubic boron nitride (CBN) wheel has perfect precision retention and high-temperature grinding performance, which is widely used in the field of grinding difficult-to-cut materials, such as nickel-based superalloy. However, the research on the influence law and mechanism of grinding surface morphology affected by the wear state of small-size grinding wheel is insufficient, which limits the further promotion and application of electroplated CBN wheel in the field of precision grinding of superalloy materials. Based on the in-depth analysis of the structure of FGH96 turbine disk, and combined with the actual processing requirements, the electroplated CBN wheel was designed, and the abrasive grains size selection experiments and CBN wheel wear experiments were then carried out for the powder metallurgy superalloy FGH96 in turn. The influence law of the abrasive grain size of CBN grinding wheel and the wear state of grinding wheel on the surface morphology was investigated, respectively. The obtained results showed that under the given processing parameters, the surface roughness Ra using 400# and 600# electroplated CBN wheels are around 0.66 μm and 0.53 μm during the normal wear state of grinding wheels, respectively, which can meet the requirement of surface quality less than Ra 0.8 μm in engineering application of turbine disk, and prove the feasibility of small-size CBN wheel grinding FGH96. In addition, the failure form of electroplated CBN wheel is mainly the accumulation and adhesion of abrasive debris, and the crushing and shedding of abrasive grain are hard to appear.