基于激光选区熔化(SLM)技术制备了Inconel 718合金,采用扫描电镜和能谱仪,分析了传统工艺和SLM技术制备的Inconel 718合金在650 ℃下氧化不同时间后表面氧化物的微观形貌和成分。结果表明:两种Inconel 718合金表面都出现了片状和块状氧化物,其氧化物的生长规律大致相同,SLM技术制备的Inconel 718合金的抗氧化性能略优于传统工艺制备的Inconel 718合金的;两种Inconel 718合金表面的片状氧化物主要由氧元素向基体内部扩散发生氧化生成,块状氧化物主要由合金元素向外扩散发生氧化生成;两种Inconel 718合金表面氧化膜的主要成分为铁的氧化物,随着氧化时间的延长,氧化物类型逐渐趋向于Me₂O₃氧化物。

Inconel 718 alloy was prepared based on selective laser melting (SLM) technology. Scanning electron microscopy and energy dispersive spectroscopy were used to analyze micro morphology and composition of oxides on the surface of Inconel 718 alloys prepared by conventional process and SLM technology, respectively, after oxidation at 650 ℃ for different periods of time. The results showed that both flake and bulk oxides appearred on the surface of the two Inconel 718 alloys, and the growth rules of oxides were roughly the same. The oxidation resistance of Inconel 718 alloy prepared by SLM technology slightly better than that of Inconel 718 alloy prepared by conventional process. The flake oxides on the surface of the two Inconel 718 alloys were mainly formed by of oxygen elements into the matrix and being oxidized, and the bulk oxides were mainly formed by the outward diffusion of alloy elements and being oxidized. The main component of oxide film on the surface of two Inconel 718 alloys was iron oxide. With the prolongation of oxidation time, the oxide type gradually tended to Me₂O₃ oxide.