Amorphous carbon based hard multilayer film for hard surface component such as sliding component of machine, has base layer containing nitride, compositional gradient layer and surface layer, sequentially formed on substrate

摘要

The amorphous carbon based hard multilayer film has base layer, compositional gradient layer and surface layer, sequentially formed on substrate. The base layer contains nitride or carbonitride of element chosen from 4A, 5A and 6A group element of periodic table, which is expressed by specific formula. The surface layer contains amorphous carbon film containing carbon of 50 atomic% or more. The amount of elements and nitrogen in compositional gradient layer are decreased, and amount of carbon is increased from base layer to the amorphous carbon film. The amorphous carbon based hard multilayer film has base layer, compositional gradient layer and surface layer, sequentially formed on substrate. The base layer contains nitride or carbonitride of element, which is expressed by formula: M 1 - x - yC xN y, where M is chosen from 4A, 5A and 6A group element of periodic table, aluminum and silicon, and x is 0.5 or less, y is 0.03 or more and 1-x-y is more than 0, which are in atomic ratio. The surface layer contains amorphous carbon film containing carbon of 50 atomic% or more. The amount of elements and nitrogen in compositional gradient layer are decreased, and amount of carbon is increased from base layer to the amorphous carbon film. The element M is chosen from titanium, zirconium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, aluminum and silicon. Preferably element is chosen from tungsten, molybdenum and tantalum.