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Grinding wheel passivation is an inevitable phenomenon during grinding process. It has important guiding significance for the formulation of grinding technique to unveil the passivation rule and generation mechanism. Taking grinding efficiency as evaluation indicator, the passivation curve of grinding wheel during full passivation period under the constant-force grinding condition is established through experiments in this dissertation, which is divided into three stages according to passivation speeds and passivation patters, i.e. early passivation stage, stable passivation stage and sharp passivation stage. Of which, the passivation speed is the slowest but with the highest grinding efficiency in early passivation stage. The change of passivation curve with the time is a process from concave to convex, which is totally different from the wearing process of grinding wheel in this stage. With combination of experiment conditions and wearing characteristics of grinding wheel, the passivation rule and its generation reasons are discussed deeply. Furthermore the exponential function y = abx is adopted to make fitting for passivation curve based on the scatter plot of stable passivation stage and regression equation is derived through the fitting result of origin thus to testify the correctness of the inference.

The compressing piston and cylinder of refrigerating compressor frequently come into failures as anti-wearability for metal material is weak. Engineering ceramics is appreciated by designers thanks to its excellent performances. However, it is difficult to machining material because of high hardness. The FEA modules for displacement and stress distributions of compressing piston and cylinder under declared running conditions are established based on the theories of elasto-plasticity and aerodynamics, which reveal the optimal precision conjugation clearance dependence of pressure distributions regularity between friction couple. Based on the FEA analytical results, the feasibility of replacing metal material with Si3N4 ceramics in the friction couple manufacture is researched. Special clamps have been designed to guarantee the superficial quality as mirror surface and tolerances of form and position, technological procedures are programmed, and with satisfactory machining effect.