304 스테인레스강의 고착방지성능 향상을 위한 Sn-Al 열 확산 코팅 기술 개발

The important drawback of hardware fasteners consisted of 304 stainless steel (STS) is a frequent galling caused by a combination of friction and adhesion between the sliding surface. To improve the anti-galling effect, Sn-Al coatings by a thermal diffusion have been developed. The thermal diffusion by pack cementation with an $AlCl_3$ activator at $250^{\circ}C$ for 1 hour produced an Sn-Al alloy coating layer with an average thickness of $9.9{\pm}0.5{\mu}m$ on the surface of 304 STS fasteners. Compared with the galling frequency of the 304 STS fasteners, Sn-Al coatings on the surface of 304 STS fasteners demonstrated about 2.8-time reduction of the galling frequency.