| 摘要 |
PURPOSE:To form a metal carbide layer with a necessary thickness on a necessary place, by a method wherein a carburization material containing carbon is applied to the surface of a metal material with reduced carbon content and the coated metal materal is heated in the presence of a powder comprising a carbide forming metal element. CONSTITUTION:A metal carbide layer having high hardness and excellent anti- wear property is applied to the surface of a metal material capable of forming solid solution with externally supplied carbon such as steel, a Ni alloy or a Co alloy or a Co alloy and extremely low in carbon content, especially, a knife having a thin sharp protruded part. On the other hand, a powder of a carburizing activator such as LiCO3 or BaCO3 is mixed in a fine powdery carbon material such as charcoal and the resulting mixture is blended with a sticky binder such as water glass to form a slurry which is in turn applied to a carbide forming place in a thickness of 0.1-1mm. to be dried thereon. In the next step, a metal of Ti, V, Nb, Ta or Cr, an alloy thereof or oxide thereof forming hard carbide is adhered to the coated caribide forming place in a powdery form and the whole is heated to 800-1,100 deg.C to simultaneously carry out carburization and the formation of carbide of the above-mentioned metal. |
