In order to improve the corrosion resisting property of ferrous metals in molten zinc, siliconizing, molybdenumizing and silicon-molybdenumizing are carried out on the Q235 steel surface by solid powder method.The infiltration layers'' morphology, compactness degree, microhardness, component and phase structure are analyzed.Moreover, the samples are soaked in the molten zinc bath at 470 ℃ for 26 h, and their corrosion rate is measured.The results show that the intermetallic compounds (Fe3Si, Fe3Mo, MoSi2 and Mo5Si3) with good corrosion resisting property are produced in infiltration layers.The addition of Mo element can promote the penetration of Si element in the infiltration agents, thus increasing the compact density of infiltration layers.The comparative results also prove that the silicon-molybdenumizing layers are more compact, especially for the sample with m(Si)∶m(Mo)=2∶1.Its corrosion rate decreases almost two orders of magnitude compared with that of the substrate, showing better corrosion resisting property.However, the existence of defects (such as holes) in the infiltration layers leads to the decrease of compact density, and the corrosion resisting property in molten zinc is also affected.Therefore, in the future studies much attention should be paid to the improvement of the compact density of solid infiltration layers, so as to further increase the corrosion resisting property.%为提高铁基金属在熔融锌中的耐蚀性能,通过固体粉末法在Q235钢表面进行渗硅、渗钼和硅钼共渗,并对渗层的形貌、致密度、显微硬度、组分及物相结构进行了分析,进一步将合金于470 ℃的熔融锌液中浸泡26 h,并测定其腐蚀速率.结果表明,渗层中形成了良好耐蚀性的金属间化合物(Fe3Si,Fe3Mo,MoSi2和Mo5Si3),Mo元素的加入可促进渗剂中Si元素的渗入,从而提高渗层的致密度,比较结果显示硅钼共渗层更加致密,尤其是m(Si)∶m(Mo)=2∶1时,与基体相比,试样的腐蚀速率下降了近2个数量级,表现出较好的耐蚀性;但由于渗层中孔洞等缺陷的存在,导致其致密度降低,耐锌液腐蚀性能也受到影响.因此在未来的研究中,应注重固体渗层致密性的改善,以进一步提高渗层的耐腐蚀性能.
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