COMPOSITE PLASMA CARBURIZING METHOD

摘要

PURPOSE: A composite plasma carburizing method is provided which not only removes carbides such as Fe3C, Fe3C7, CrC2 and Cr7C2 formed on the surface of a metallic material but also improves carburizing rate due to the surface cleaning and activation by repeatedly performing sputtering, decarburizing and diffusing processes in the plasma decarburizing process. CONSTITUTION: In a surface hardening method carburizing using plasma, the composite plasma carburizing method comprises the processes of removing an oxide film of the surface of a sample by an inert gas at a carburizing temperature in the sputtering process; carburization heat treating the reactants after reacting an ionized carbon atom or activated carbon atom by the generation of plasma with the sample; performing diffusion process after passing through the sputtering process of decarburizing, cleaning of the surface and activating of the surface by plasma of a mixed gas. In a surface hardening method carburizing using plasma, the composite plasma carburizing method comprises the processes of performing the diffusing process and the cooling process after reducing a flow rate of hydrocarbon gas continuously or in stages during the plasma process.