【摘 要】
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The engineering ceramic grinding process with an electroplated diamond wheel is significantly influenced by the detrimental effect of the grain dislodgement which causes surface roughness degradation
【机 构】
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Department of Mechanical Engineering, Tsinghua University, Beijing, 100084, China
论文部分内容阅读
The engineering ceramic grinding process with an electroplated diamond wheel is significantly influenced by the detrimental effect of the grain dislodgement which causes surface roughness degradation and tool life decrease.Therefore,the thickness of the electroplated bond layer must be large enough to provide sufficient micro-bonding force to overcome the single grain micro-cutting force during grinding.However,large electroplated bond layer thickness hampers the protrusion condition of the grains,and causes insufficient active grains.The conventional ‘trial and error method based on heuristic knowledge currently appears to be the only way in developing electroplated diamond wheels.The difficulty of a deterministic wheel design lies in the lack of an integrated model to predict micro-bonding force and protrusion conditions of all diamond grains on the wheel surface for a given grain size,dimensional distribution,and bond layer thickness.In this paper,the digital grinding wheel model is developed for single layer electroplated diamond wheels by simulating each wheel fabrication procedure numerically.The model provides a 3D view of the wheel surface condition and micro-bonding force,protrusion information in correlation with the wheel design parameters,e.g.grain size,dimensional distribution and bond layer thickness.Based on the analysis of the micro-cutting force on a single grain during grinding,the optimal electroplated bond layer thickness can be determined.Finally,a grinding experiment for an alumina engineering ceramic is carried out to verify the efficacy of the model in the development of dislodgement free diamond wheels.
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