离子氮化处理对涂层组织与耐磨性能的影响

Effect of Ion Nitriding Treatment on Microstructure and Anti Wear Properties of NiCrBSi Self Fluxing Alloy Coating

研究了NiCrBSi自熔合金炉熔涂层的离子氮化后处理工艺 ,考察了离子氮化处理对涂层组织与耐磨性能的影响。结果表明 ,NiCrBSi合金涂层经离子氮化处理后 ,在其表面区 (宽度约 50 μm)形成了弥散分布的尺寸小于 5μm的颗粒状氮化物相 (如CrN、BN等 ) ,表面硬度从 80 0HV0 .0 1 提高到 130 0HV0 .0 1 左右 ,耐磨性能因此得以显著提高 ,从 38CrMoAl氮化钢的 2 0 %～ 2 5%提高到优于氮化钢 2～ 3倍。由于已存在高硬度WC颗粒相的强化作用 ,含 2 0

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.