| 摘要 |
PROBLEM TO BE SOLVED: To obtain a composite film having good adhesion to the base body and a small coefft. of friction by forming a first film containing no hydrogen as the lower layer to be in contact with the base body and forming a second film containing hydrogen as the upper layer which slides on a sliding material. SOLUTION: This first diamond like carbon(DLC) film is formed by the vacuum arc method using solid carbon such as graphite, and the second DLC film is formed by the plasma CVD method using hydrocarbon gas such as methane. The thickness of each film is 0.2 to 5 μm, and another DLC film may be formed between the upper and lower layers. By forming an intermediate layer consisting of DLC or the like containing metals such as W, Ti, Nb and Si having higher carbide forming performance than the metal material of the base body, still higher adhesion property is obtd. The coefft. of friction of the first DLC film provided on a W intermediate layer is as large as about 0.6 in the initial state and decreases to 0.4 with increase in the sliding distance, while the coefft. of friction of the second DLC film is as small as 0.2 and does not change with the sliding distance. |
