Case Hardening and Coatings for Wear Protection

Jun Qu (Oak Ridge National Laboratory)

Abstract

Surface engineering is an effective approach for wear protection. This presentation provides an overview of ORNL’s tribological research of various hard coatings and case-hardening surface treatments for applications in transportation, hydraulics, and machining in last two decades. Examples include oxygen-diffusion for titanium [1], low-temperature carburization for austenitic stainless steels [2], iron boriding and chromizing for tool and carbon steels [3], chromium nitride (CrN) coating [4], composite boride (AlMgB14-TiB2) coating [5], and diamond-like-carbon (DLC) coating [6]. Comprehensive materials characterization was used to examine the microstructure and composition of the near surface zone and correlate with the hardness, friction coefficient, and wear rate for revealing the surface protecting mechanisms and compatibility with the lubricant chemistry. Limitations in applicability and operating conditions will also be discussed for each type of surface treatments. 

References

1. Scripta Materialia 60 (2009) 886; Wear 267 (2009) 818; Tribology International 136 (2019) 342. 
2. Wear 263 (2007) 719; Wear 265 (2008) 1909; Wear 271 (2011) 1733
3. Wear 522 (2023) 204714; Advances in Applied Ceramics 122 (2023) 215
4. Tribology International 160 (2021) 107010
5. Surface and Coatings Technology 205 (2010) 2296; Wear 271 (2011) 2111; Wear 332-333 (2015) 1273; Advanced Materials Interfaces (2015) 1500213; Tribology International 99 (2016) 182
6. Wear 332-333 (2015) 1273; Advanced Materials Interfaces (2015) 1500213; Tribology International 99 (2016) 182; Tribology International 160 (2021) 107010; Wear 522 (2023) 204714