Mechanical, Tribological, and Oxidation Resistance Properties of NiCrAlY Coating by Atmospheric Plasma Spraying

Bo Li,Yimin Gao,Shengqiang Ma,Qiaoling Zheng,Cong Li,Junhong Jia,Yunchuan Kang,Hongjian Guo

doi:10.3389/fmats.2019.00067

Abstract

In this paper, the NiCrAlY coating was prepared by atmospheric plasma spraying (APS) and the influence of heat treatment on the mechanical property, tribological property and oxidation resistance property of coating were researched. The coating was heat-treated at 900 oC and 1100 oC, respectively. The microstructure of coating became more homogeneous after heat treatment. Meanwhile, heat treatment could effectively increase the microhardness and adhesive strength as well as decrease the porosity of coating. The coating presented the highest adhesive strength of 62.1 MPa and the lowest porosity of 3.06 % as well as the excellent tribological property and oxidation resistance property at 900 oC after 1100 oC heat treatment.

Highlights

The NiCrAlY coating was fabricated by atmospheric plasma spraying (APS) (SulZer Metco 9 M, US)
It can be clearly seen that the powder is spherical in shape with sizes of 53–106 μm (Figure 1a)
The spherical shape powder has an excellent flowability, which is very useful for the feeding rate during the spray process

Summary

INTRODUCTION

Over the past few decades, MCrAlY (M = Nickel or/and Cobalt) coatings act as a kind of representative metal-based protective coating that are widely used in several industries such as gas turbines and aircraft engines (Zhao et al, 2004; Vilar et al, 2009; Tahari et al, 2012; Di Leo et al, 2014; Yaghtin et al, 2014; Li et al, 2016, 2017c; Amann et al, 2018). Because the gas turbine engines are exposed in the dusty environment, the stability and lifetime of coatings could deteriorate (Zhao et al, 2004; Li et al, 2017c) These coatings should show an excellent mechanical strength, wear resistance, hardness, and oxidation resistance at high temperature (Hou et al, 2015). The present work aimed to investigate the effect of heat treatment on the microstructure, mechanical property, tribological property, and oxidation resistance property of the NiCrAlY coating

MATERIALS AND METHODS

RESULTS AND DISCUSSION

CONCLUSIONS