Surface and Subsurface Characteristics of NiCrBSi Coating with Different WC Amount Prepared by Flame Spray Method
- 29 Downloads
This research aims at understanding the spray coating of NiCrBSi with different amount of tungsten carbide particles on JIS SUP9 steel substrate. The amount of tungsten carbide added to NiCrBSi was 0, 20, and 40% by volume to reinforce the coating. Microstructures, microhardness, adhesion, cohesion, and rigidity of coating were characterized. The results revealed that NiCrBSi structure composed of nickel solid solution as matrix embedded with Ni boride and Ni4Si with chromium carbide distributed across the coating. Tungsten carbide particles were apparent in the coating and they partially diffused into the NiCrBSi coating. In the case of 40% tungsten carbide addition, the matrix hardness was increased by 29.18%, but the cohesion of coating was reduced by 22.94%. The adhesion failure was not apparent in all samples examined in this study under the 20 N scratch load. Wear area of coatings mixed with tungsten carbide addition was found to decrease by 3.5 to 8.8 times compared to the substrate. As per the findings, the addition of WC can promote the wear resistance by its reinforcement and also introduce the solid solution strengthening of W in the NiCrBSi matrix, specifically in the Ni solid solution.
KeywordsNiCrBSi coating solid solution strengthening thermal spray coating tungsten carbide
This work is a part of “Application of Thermal Spray in Agricultural Part” project, supported by Innovation and Technology Assistance Program (iTAP) under National Science and Technology Development Agency (NSTDA) and Acme International (Thailand) Ltd. The authors would like to express their gratitude and gratefully acknowledge.