(1. 蘭州理工大學 甘肅省有色金屬新材料省部共建國家重點實驗室，蘭州 730050；
2. 蘭州工業(yè)高等專科學校 材料工程系，蘭州 730050)
摘 要: 以n(NaCl):n(KCl):n(NaF)=2:2:1堿金屬鹵化物混合體系做載體，采用不同摩爾比的Na2SiF6和Si粉作滲硅劑，在800 ℃下利用熔融鹽法分別對AISI 304不銹鋼進行滲硅處理。采用X射線衍射儀(XRD)分析滲硅層的物相組成，用附帶能量色散譜儀(EDS)附件的掃描電子顯微鏡(SEM)研究滲層截面的形貌和成分，分析熔鹽法滲硅層的形成機理。結(jié)果表明：融鹽中SiF62−的濃度決定滲層中Si元素的含量，由于SiO2在融鹽體系中的溶解，融鹽中SiF62−得到補充，滲層中Si元素的含量進一步提高。
關(guān)鍵字: AISI 304不銹鋼；Fe3Si；硅化物滲層；滲硅機理；滲硅體系
（1. State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials, Lanzhou University of Technology,
Lanzhou 730050, China;
2. Department of Materials Engineering, Lanzhou Polytechnic College, Lanzhou 730050, China）
Abstract:The silicide layers deposited on the AISI 304 stainless steel were formed in the molten salts at 800 ℃ using the molten mixture of different mole ratios of Na2SiF6 to Si using the siliconizing agent and the molten halogenide of alkali metals of NaCl+KCl+NaF at mole ratio of 2:2:1 as the siliconizing agent carrier. In order to reveal the siliconizing mechanism in the molten salts, the phase of the silicide layer was analyzed by X-ray diffractometry. Meanwhile, the micrographs and the composition of the cross section of the silicide layer were studied by scanning electron microscopy (SEM) attached with energy dispersive X-ray spectrometer (EDS). The results show that the silicon content in the layer depends on the ion concentration of SiF62− in the molten salts. The dissolving of SiO2 in the molten salts supplies the SiF62− continuously and as a result, the silicon content in the layer is enhanced.
Key words: AISI 304 stainless steel; Fe3Si; silicide layer; siliconizing mechanism; siliconizing system
