稀有金属材料与工程
稀有金屬材料與工程
희유금속재료여공정
RARE METAL MATERIALS AND ENGINEERNG
2009年
7期
1146-1149
,共4页
镍基高温合金%石墨%氧化动力学%氧化机制
鎳基高溫閤金%石墨%氧化動力學%氧化機製
얼기고온합금%석묵%양화동역학%양화궤제
Ni-based superalloy%graphite%oxidation kinetics%oxidation mechanism
采用粉末冶金方法制各不同石墨含量(0%、3%、6%)的镍基高温合金,研究合金材料在900℃和100 h下的恒温氧化行为,用扫描电镜和X射线衍射对其氧化表面形貌和成分进行观察和分析.结果表明:石墨含量较低(0%,3%)时,镍基合金氧化动力学符合抛物线规律,表面氧化膜无剥落;石墨含量为0%的合金氧化膜由Cr2O3和NiCr2O4组成,石墨含量为3%的合金氧化膜由Cr2O3组成,当石墨含量增加到6%时,大量石墨的氧化分解导致合金初始氧化严重,石墨分解后的孔洞加速氧化反应过程.根据氧化膜的组成分析了合金的氧化机制.
採用粉末冶金方法製各不同石墨含量(0%、3%、6%)的鎳基高溫閤金,研究閤金材料在900℃和100 h下的恆溫氧化行為,用掃描電鏡和X射線衍射對其氧化錶麵形貌和成分進行觀察和分析.結果錶明:石墨含量較低(0%,3%)時,鎳基閤金氧化動力學符閤拋物線規律,錶麵氧化膜無剝落;石墨含量為0%的閤金氧化膜由Cr2O3和NiCr2O4組成,石墨含量為3%的閤金氧化膜由Cr2O3組成,噹石墨含量增加到6%時,大量石墨的氧化分解導緻閤金初始氧化嚴重,石墨分解後的孔洞加速氧化反應過程.根據氧化膜的組成分析瞭閤金的氧化機製.
채용분말야금방법제각불동석묵함량(0%、3%、6%)적얼기고온합금,연구합금재료재900℃화100 h하적항온양화행위,용소묘전경화X사선연사대기양화표면형모화성분진행관찰화분석.결과표명:석묵함량교저(0%,3%)시,얼기합금양화동역학부합포물선규률,표면양화막무박락;석묵함량위0%적합금양화막유Cr2O3화NiCr2O4조성,석묵함량위3%적합금양화막유Cr2O3조성,당석묵함량증가도6%시,대량석묵적양화분해도치합금초시양화엄중,석묵분해후적공동가속양화반응과정.근거양화막적조성분석료합금적양화궤제.
Nickel-based alloys with different contents of graphite were prepared by powder metallurgy method.High temperature oxidation resistance of these alloys was studied by high temperature test at 900 ℃ for 100 h in static air.Morphology of oxides was studied by SEM and their composition was analyzed by XRD.The result shows that the kinetic curves of oxidation for nickel-based alloys with lower content of graphite obey the parabolic law.The oxide films consist of Cr2O3 and NiCr2O4 when the alloy contains no graphite.The oxide film consists of Cr2O3 when the alloy contains 3% graphite.If graphite content increases to 6%,the oxidative decomposition of graphite leads to severe initial oxidation,and mass gain takes place significantly; the cavity after decomposition of graphite accelerates the process of oxidation reaction.The oxidation mechanism of the alloy has also been suggested by the phase composition analyses of oxide film.
