Multi-layer Coating Having Excellent Adhesion and Sliding Properties and Production Method Thereof: No. 7,485,372; Ken Inoue and Kenichi Inoue, assignors to Hitachi Metals, Ltd., Tokyo, Japan.
A multi-layer coating with excellent adhesion and sliding properties has been patented. It has a hard layer with a main component of a nitride and/or carbonitride of one or more elements selected from the group consisting of Ti, V, Zr, Cr, Nb, Si, A1 and B. It also features a lubricating layer consisting of a metal element and molybdenum disulfide on the hard layer. The lubricating layer has a graded composition in which the metal element has a decreasing content from the hard layer side toward the surface and the molybdenum disulfide has an increasing content. The lubricating layer has a maximum oxygen concentration of no greater than 25 atom percent and a thickness of 0.5 [micro]m or more.