Structural and Phase Transformations on the Surface of Spark-Laser Coatings under Fretting Corrosion in AIr

 
I.Podchernyaeva,
 
A.I.Dukhota,
 
A.Panasyuk
 

I. M. Frantsevich Institute for Problems of Materials Science of the NAS of Ukraine, Krzhizhanovsky str., 3, Kyiv, 03142, Ukraine
Powder Metallurgy - Kiev: Frantsevich Institute for Problems of Materials Science NASU, 2012, #01/02
http://www.materials.kiev.ua/article/991

Abstract

The structure and phase transformations on the surface of a ZrB2-based combined laser-spark coating on titanium alloy are studied. The transformations are induced by triboprocesses under fretting corrosion in air. It is shown that the surface transformations result from a combination of three mechanisms: plastic strain (surface texture, fatigue, crack formation, brittle fracture); oxygen diffusion from the environment and chemical reactions of tribooxidation and diffusion of substrate elements (Al) toward the wear surface; and removal of particles from the surface. Two-phase nanostructured eutectic is found on the wear surface of the combined coating.


FRETTING, LASER-SPARK COATING, STRUCTURE AND PHASE TRANSFORMATIONS, TRIBOFILM, ZIRCONIUM BORIDE