(1. 中南大學 粉末冶金國家重點實驗室,長沙 410083;
2. 西北有色金屬研究院 金屬多孔材料國家重點實驗室,西安 710016)
摘 要: 研究Ni-Cr-Al-Fe基合金粉末在600 ℃空氣中的高溫抗氧化性能,分析鋁含量和預氧化處理對合金粉末高溫抗氧化行為的影響。利用水霧化法制備不同鋁含量的Ni-Cr-Al-Fe基合金粉末,利用靜態(tài)質(zhì)量增加法研究不同鋁含量合金粉末的氧化動力學,分別利用FE-SEM(EDS)和XRD觀察分析不同合金粉末氧化膜的形貌及成分,結合氧化動力學及氧化膜的組成進一步分析不同合金粉末的高溫氧化機理。結果表明:Ni-Cr-Al-Fe基合金粉末在600 ℃時的氧化質(zhì)量增加遵循拋物線規(guī)律,鋁含量的增加及預氧化處理均可提高合金粉末的抗氧化能力;鋁含量的增加使氧化膜的組成由Cr2O3和Al2O3的混合結構轉變?yōu)閱我坏腁l2O3氧化膜結構,這有利于提高合金粉末的抗氧化性能;預氧化處理所形成的氧化膜有效地抑制Ni-Cr-Al-Fe基合金粉末的進一步氧化。
關鍵字: Ni-Cr-Al-Fe基合金粉末;高溫抗氧化性;預氧化;氧化機理
Ni-Cr-Al-Fe based powders
(1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
2. State Key Laboratory of Porous Metals Materials, Northwest Institute for Nonferrous Metal Research, Xi’an 710016, China)
Abstract:The oxidation resistance of Ni-Cr-Al-Fe based powders at 600 ℃ was investigated, and the effects of aluminum content and pre-oxidation treatment on its oxidation resistance behavior were analyzed. The Ni-Cr-Al-Fe based powders were prepared by water atomization. The oxidation kinetics was investigated by conducting the mass increase analyses. The morphology and chemical composition of the oxide films were characterized by FE-SEM (EDS) and XRD, respectively. The oxidation mechanisms of the alloy powders were also discussed by comprehensive analysis of oxidized kinetics and the phase composition of oxide layers. The results indicate that the oxidized kinetic curves of Ni-Cr-Al-Fe based powders at 600℃ follow the parabolic rule. The increase of the aluminum content and the pre-oxidation can enhance the oxidation resistance of Ni-Cr-Al-Fe based powders. With the increase of aluminum content, the oxide film changes from a combined structure of Cr2O3 and Al2O3 to single Al2O3 structure, which is beneficial to the increase oxidation resistance of Ni-Cr-Al-Fe based powders. The further oxidation of Ni-Cr-Al-Fe based powders can be effectively controlled after the pre-oxidation treatment.
Key words: Ni-Cr-Al-Fe based powders; high-temperature oxidation resistance; pre-oxidation; oxidation mechanism


