학술논문

Structure, Phase Composition, and Wear Mechanisms of Plasma-Sprayed NiCrSiB-20 wt.% TiB Coating.
Document Type
Article
Source
Powder Metallurgy & Metal Ceramics. Mar2015, Vol. 53 Issue 11/12, p663-671. 9p.
Subject
*PLASMA spraying
*SURFACE coatings
*SINTERING
*TITANIUM diboride
*FRICTION
Language
ISSN
1068-1302
Abstract
The structure, phase composition, and wear mechanisms of plasma-sprayed NKhTB20 coating (NiCrSiB-20 wt.% TiB) are studied. To produce NKhTB20 composite powder, commercial PR-NKh16SR3 (NiCrSiB) powder was mixed with 20 wt.% TiB and the charge was pressed and sintered in vacuum at 1100°C for 30 min. During sintering, the components react to form chromium borides. The sinters were ground and classified into the particle size fraction -100+60 nm for plasma spraying. The plasma-sprayed NKhTB20 coating consists of a nickel-based matrix reinforced with titanium diboride and chromium boride grains. The friction and wear behavior of the NKhTB20 coating in dry friction against plasma-sprayed NiCrSiB and NKhTB20 coatings is examined. It is revealed that the NKhTB20/NiCrSiB friction pair has higher wear resistance than NKhTB20/NKhTB20. The contact surfaces of the NKhTB20/NKhTB20 friction pair are damaged under oxidative and abrasive wear mechanisms. Oxidative wear is the dominant mechanism for the NKhTB20/NiCrSiB friction surface. Complex oxide films form on the NKhTB20/NiCrSiB sliding surface and prevent it from damage. [ABSTRACT FROM AUTHOR]