不同基体材料TD法盐浴渗钒层的组织及硬度

Microstructure and hardness of vanadium carbide coatings prepared by thermal diffusion process on different steel substrate

通过对45、T10、T12、W6Mo5Cr4V2、GCr15、Cr12MoV钢六种不同的基体进行盐浴渗钒,并对渗钒层的组织、厚度、成分和硬度进行测试比较。结果表明,基体化学成分对覆层的厚度、成分和硬度均有影响。基体中的固溶碳含量能促进覆层的生长,增加覆层厚度,提高覆层中的C/V浓度比,改善覆层硬度。而且,对覆层的能谱分析结果表明在碳素钢基体上的覆层中只含有C、V、Fe三种元素,而在合金钢基体上的覆层中还探测到了少量的来自基体的合金元素,这些合金元素向覆层中的扩散可以显著提高覆层的显微硬度。

Vanadium carbide coatings on 45,T10,T12,W6Mo5Cr4V2,GCr15 and Cr12MoV steel substrate were prepared by thermal diffusion process.Microstructure,thickness,chemical composition and hardness of the vanadium carbide coatings formed on different steels were investigated and compared by optical microscope,hardness tests and EDS analysis.The results show that increase of dissolved carbon content in substrate can accelerate coating growth,increase coating thickness,enhance C/V ratio in vanadium carbide coating and improve coating hardness.The results of energy dispersive spectrometer analysis reveal that there are only C,V and Fe elements in the coatings formed on carbon steel substrate,however,excepting of C and V and Fe elements,a small quantity of alloy elements from substrate are detected in the coatings formed on alloyed steel substrate.The diffusion of alloy elements into coatings can greatly increase the microhardness of vanadium carbide coatings.