| 摘要 |
PURPOSE:To carburize rapidly a high Cr alloy steel contg. a specified percentage or more of Cr with simple equipment without causing intergranular oxidation by adding a specified percentage or more of gaseous hydrocarbon to gaseous nitrogen introduced into a furnace and by carburizing the steel at a prescribed high frequency heating temp. CONSTITUTION:A high Cr alloy steel having >=10% Cr content is heated with a high frequency coil and carburized at 1,000-1,200 deg.C high temp. at which no melting phenomenon is caused in an atmosphere of gaseous nitrogen contg. >=1% hydrocarbon. Since the oxygen potential is low, a satisfactory carburized surface layer is rapidly formed without causing intergranular oxidation. This method is carried out very efficiently with simple equipment. When the Cr content of the base material is <=10wt%, the carburizing speed is reduced. |
