Design of low-friction PVD coating systems with enhanced running-in performance - carbon overcoats on TaC/aC coatings

SURFACE & COATINGS TECHNOLOGY

卷:222

Article

Nyberg, Harald¹  Tokoroyama, Takayuki^1,2  Wiklund, Urban¹  Jacobson, Staffan¹ 

[1] Uppsala Univ, Dept Engn Sci, Tribomat Grp, SE-75121 Uppsala, Sweden

[2] Nagoya Univ, Dept Mech Sci & Engn, Chikusa Ku, Nagoya, Aichi 4648603, Japan

关键词: Low friction coatings;    Surface roughness;    Running-in;    PVD DLC;   

DOI  :  10.1016/j.surfcoat.2013.02.003

来源: Elsevier

【 摘 要 】

The widespread use of low friction PVD coatings on machine elements is limited by the high costs associated with fulfilling the demands on the surface quality of both the supporting substrate and the counter surface. In this work, an attempt is made at lowering these demands, by adding a sacrificial carbon overcoat to a TaC/aC low friction coating. Both coatings were deposited by planar magnetron DC sputtering, as separate steps in a single PVD-process. Coatings were deposited on substrates of two different surface roughnesses, in order to test the ability of this coating system to function on rougher substrates. Reciprocating ball on disc tests was performed, using balls with two different surface roughnesses. The worn surfaces were investigated using 3-D profilometry and SEM. The ability of the different overcoats to initially reduce the roughness of both the coated surface and the counter surface and to produce stable, low-friction conditions was examined for the different initial roughnesses. The implications for design of efficient run-in coatings for various systems are discussed. (c) 2013 Elsevier B.V. All rights reserved.

【 授权许可】

Free