Effect of Ion Nitriding Treatment on Microstructure and Anti Wear Properties of NiCrBSi Self Fluxing Alloy Coating
XIANG Xing hua 1, LIU Zheng yi 1, ZOU Gan feng 1, ZHU Hui zhao 2(1. Department of Electro Mechanical Engineering, South China University of Technology, Guangzhou 510640; 2. Guangzhou Institute of Nonferrous Metals, Guangzhou 510651, China)
The influence of ion nitriding process was investigated on microstructure and anti wear properties of NiCrBSi self fluxing alloy coating that was fabricated by plasma spraying and re melted in furnace. Results showed that some very hard CrN and BN particles (the size was less than 5 μm) were formed on the surface zone of coating (the width was about 50 μm), whose micro hardness was increased from 800 HV 0.01 to 1 300 HV 0.01 after ion nitriding treatment at 540 ℃ for 8 h. The anti wear of NiCrBSi alloy coating was improved remarkably by ion nitriding process as changes from 20%～25%to 2～3 times higher than 38CrMoAl nitriding steel, but the anti wear of Ni composite coating with 20% WC could not be improved by ion nitriding process.