学术论文摘要示例
发布人:editor158 发布时间:2013/7/4 9:15:05  浏览次数:1051次
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光束合金化合成Fe-Al系金属间化合物涂层的微观特征[示例]

摘要:[目的]为了改善钢铁材料的耐高温腐蚀性能, [过程和方法]用光束合金化方法在45钢表面合成了Fe-Al金属间化合物涂层.采用扫描电子显微镜、能量弥散X射线分析和X射线衍射研究了光束合金化工艺参数(粉末预置量m和热输入量q)对合金化层的化学成分、显微组织及其物相组成的影响. [结果]实验结果表明: 减小比能量(E=q/m)将导致合金化层的熔宽和熔深减小, 从而使合金化层含Fe量减少, 含Al量增加;该实验条件下, 获得了Fe与Al原子数比为2.4~19.2的合金化层. 由比能量决定的Fe与Al原子数比是合金化层显微组织及其物相组成的重要影响因素, 合金化层的显微组织有3种类型: α-Fe固溶体、α-Fe固溶体+Fe3Al金属间化合物及FeAl+AlFe3C0.5金属间化合物. [结论]降低热输入或增加粉末预置量均可引起合金化层中Fe与Al原子数比的降低,有助于Fe-Al系(Fe3Al或FeAl)金属间化合物的合成.

关键词:表面合金化; Fe-Al金属间化合物; 光束合金化涂层; 微观组织; 物相

Microstructure characteristics of Fe-Al intermetallic compound coating synthesized by light beam alloying [Example]

Abstract: The high temperature corrosion resistance of steel was improved with a Fe-Al intermetallic coating applied to Steel-45 by light beam alloying. The effect of alloying processing parameters (the pre-placed powder mass, m, and the heat input, q) on the chemical composition, microstructure and phases of the alloying coatings was investigated by scanning electron microscopy, energy dispersive X-ray analysis, and X-ray diffraction. The results show that reducing the specific heat input E (E=q/m) reduces the width and penetration of the alloying molten pool, which reduces the Fe content and increases the Al content of the coatings. The experiments resulted in coatings with 2.4-19.2 Fe/Al atomic ratios. The Fe/Al atomic ratio determined by the specific heat input is the most important factor affecting the microstructure and phases of the coatings. There are three kinds of coating microstructures, α-Fe solid solution, α-Fe solid solution + Fe3Al intermetallic compound, and FeAl + AlFe3C0.5 intermetallic compounds. Reducing the heat input and increasing the pre-placed powder mass both reduce the Fe/Al atomic ratio of the coatings, which favors the synthesis of the Fe-Al(Fe3Al and FeAl) intermetallic compounds.

Key words: surface alloying; Fe-Al intermetallic compound; light beam alloying coating; microstructure; phases