304不锈钢双辉等离子渗铜铪表面合金层组织及抗菌性能

Microstructure and Antibacterial Properties of Cu-Hf Alloying Layer on 304 Stainless Steel Through Double Glow Plasma Technology

利用双辉渗金属技术在304不锈钢表面进行铜铪共渗,使用光学显微镜、X射线衍射仪和扫描电镜研究铜铪共渗合金层的显微组织、相结构、形貌、成分和表面硬度,采用薄膜密贴法对合金层进行抗菌性能的检测。结果表明:铜铪共渗合金层由扩散层和沉积层构成,合金层表面组织致密、分布连续、无明显裂纹和孔隙。铜、铪含量由表至里逐渐减少,渗铜铪试样中的铬和碳都出现向渗层表面迁移的现象。抗菌检测中,铜铪合金层表面对大肠杆菌和金黄色葡萄球菌都具有优良的抗菌性能,抗菌率均达到99%以上。当铜在源极棒中比例达到80%和90%时,所得到的渗铜铪试样抗菌率分别为99.83%和99.12%,当铜比例为70%时得到渗后试样的抗菌率仅为93%。渗后试样表面硬度约为605 HV0.1,大于渗铜试样和304不锈钢表面硬度。

Cu-Hf alloying layer was prepared on 304 stainless steel surface through double glow plasma alloying technology. The microstructure, phases, morphologies and microhardness of Cu-Hf alloying layer were investigated by OM, XRD, SEM and micro-hardmeter. The antibacterial properties of the alloy layer were tested by a coating film method. The results show that the Cu-Hf alloying layer is composed of diffusion layer and deposition layer, and the surface of the alloy layer is dense and continuous without obvious cracks and pores. The contents of copper and hafnium decrease gradually from the surface to the inside, and the chromium and carbon of the Cu-Hf alloying layer are migrated to the surface of the carburized layer. In the antibacterial test, the alloy surface exhibits excellent antibacterial properties against both E. coli and Staphylococcus aureus, and the antibacterial rate is more than 99%. When the proportion of copper in the source rods reaches 80% and 90%, the antibacterial rates of the Cu-Hf alloying layer are 99.83% and 99.12%, respectively. When the proportion of copper in the source rods is 70%, the antibacterial rate of the Cu-Hf alloying layer is only 93%. The surface hardness of the Cu-Hf alloying layer is about 605 HV0.1, which is significantly higher than the surface hardness of the Cu-alloying layer and 304 stainless steel.