等离子原位合成Ni-Al金属间化合物涂层的组织与性能研究

利用等离子激发原位反应在碳钢表面合成了Ni—Al金属间化合物涂层。借助金相显微镜、扫描电镜、 X射线衍射仪和显微硬度计对涂层的组织和性能进行了研究。结果表明:当Ni和Al的质量百分比为4:1时,涂层与基体呈冶金结合,无裂纹和气孔等缺陷;涂层的主要组成相为Ni3Al和NiAl;涂层组织为细密的树枝晶;涂层的硬度高于基体,硬度可达630HV;涂层耐蚀性能良好。

Study on Microstructure and Properties of Plasma In-situ Synthesis of Ni-Al Intermetallics Coating

Plasma excitation was used for in-situ synthesis of Ni-Al intermetallics coating. The microstructure and properties of the coating were investigated by optical microscope, scanning electron microscope, X-Ray diffractometer and microhardness tester. The results show that excellent bonding between coating and carbon steel substrate is ensured by the strong metallurgical interface, and the coating is uniform, continuous and almost defect-free when mass percent of Ni powder and Al powder is 4:1. The microstructure of the intermetallics coating is mainly composed of Ni3Al and NiAl, which is synthesized by in-situ. The microstructures of intermetallics coating is dense fir-tree crystal. The maximum microhardness of the coating is 630HV, which is higher than steel substrate. The performance of Ni-Al intermetallics coating is good.