【作者】 赵运兴； 刘军； 王薪； 江亮；

【Author】 Zhao Yunxing;Liu Jun;Wang Xin;Jiang Liang;State Key Laboratory of Powder Metallurgy,Central South University;Powder Metallurgy Research Institute,Central South University;School of Materials Science and Engineering,Central South University;

【机构】 中南大学粉末冶金国家重点实验室； 中南大学粉末冶金研究院； 中南大学材料科学与工程学院；

【摘要】 研究了一种新型单晶高温合金的在1100℃和1150℃下大气环境中的高温氧化行为,一共进行了350个循环。在两个温度下,氧化层的生长速度和时间都呈类抛物线关系,这是由于在氧化层底部生成了一层致密的Al₂O₃层。采用SEM观察分析了氧化层表面形貌和氧化层截面的微观组织。使用XRD和EDS分析氧化层的成分和元素分布。在较高的温度下,生成的氧化层较厚,而且最后的重量变化也更大,表明在更高的温度下,合金的氧化抗性越差。在两个温度下,形成的氧化层都可以分为三层:最外层的NiO层,由TiO₂,Ta₂O₅和CrO组成的中间层和最内层的致密的Al₂O₃层。而且,在合金基体和氧化层之间存在一个γ′相消失区域,氧化温度越高,这个区域的厚度越厚。更多还原

【Abstract】 The cyclic oxidation behavior of a new single crystal superalloy was investigated at 1100℃ and 1150℃,covering350 cycles in static air.A subparabolic time dependence of the growth rate of the oxide scale was detected at both temperatures due to the formation of an inner Al₂O₃ layer.The microstructure of the oxide surface and the cross section morphology were analyzed by SEM.XRD and EDS were used to identify the compositions of the oxides and element concentration.The alloy showed better resistance of oxidation at lower temperature,which can be proved by the thicker oxide scale and higher mass gain at 1150℃.The scales consist of three different layers at each temperature;A NiO containing top oxide layer,a second layer consists of TiO₂,Ta₂O₅ and CrO,an inner continuous A1₂O₃ layer close to the substrate.Moreover,a γ’ free zone was detected between the oxide scale and the substrate at both temperatures.更多还原