Correlation of Microstructure and Tribological Properties of Mo Blended Fe-Base Coatings Fabricated by Atmospheric Plasma Spraying

Lee, Illjoo; Park, Hyungkwon; Lee, Changhee

doi:2014.32.5.495

J Weld Join > Volume 32(5); 2014 > Article

Research Paper

Journal of Welding and Joining 2014;32(5):495-501.
DOI: https://doi.org/10.5781/JWJ.2014.32.5.65 Published online October 30, 2014.

Correlation of Microstructure and Tribological Properties of Mo Blended Fe-Base Coatings Fabricated by Atmospheric Plasma Spraying

Illjoo Lee^*, Hyungkwon Park^*, Changhee Lee^*

Correspondence: Changhee Lee,
Email: chlee@hanyang.ac.kr

Abstract

Atmospheric plasma spraying (APS) is world-widely used process in the automotive industry as a method to provide wear resistance coatings for engine cylinder bore, using various materials. The weight of engine blocks can be considerably decreased by removing cast iron liners, which can finally result in the improvement of fuel efficiency. In this study, five kinds of powder materials, 1.2C steel powder and 1.2C steel powder mixed with 5, 10, 15, 20 wt.%. molybdenum powder, were deposited by atmospheric plasma spraying in order to investigate the effect of molybdenum on the wear resistance of coatings. Microstructural analysis showed that molybdenum splats were well distributed in 1.2C steel matrix with intimate bonding. The molybdenum added coatings showed better tribological properties than 1.2C steel coating. However, above the 15 wt.%. blending fraction, wear resistance was somewhat degraded with poor roughness of worn surface due to the brittle fracture occurred in molybdenum splats. Consequently, compared to conventional liner material, gray cast iron, 10 wt. pct. molybdenum blended 1.2C steel coating showed much better tribological properties and therefore it looks very feasible to replace gray cast iron liner.

Key Words: Atmospheric plasma spraying, Mo blended Fe-base coating, Microstructure, Wear resistance, Mechanical property