抄録
The cause of uneven surface of titanium carbide (named TiC) layer often observed, when TiC was deposited by CVD process on iron base tool materials such as SUS440C, SKH9, SKD61, etc. (according to JIS), has been studied. It was assumed that, when CVD atmosphere having considerably high carbon potential was applied, iron atoms diffused from substrates in the layer during treatment to realize (TiC+Fe) two phase or (TiC+Fe+Fe2Ti) three phase equilibrium. However, the diffusion of iron atoms across the interface was not always uniform, Large Fe rich-region locally formed in the layer acted as a source of radiated columnar structure of TiC, resulting in the uneven surface. Detailed discussion concerning the phenomena was given.
