论文部分内容阅读
采用氧化增重实验、XRD、SEM以及EDS研究了925合金在均匀化温度1130~1190℃时的高温氧化行为。结果表明,925合金完全均匀化需要在1160℃保温20 h以上。均匀化中形成的氧化膜由内至外分为3层,分别为TiO_2层、Cr_2O_3层以及由TiO_2和尖晶石结构的Cr、Fe氧化物构成的外层。均匀化时间超过20 h,Cr_2O_3层开始减薄,并且尖晶石状Cr、Fe氧化物部分剥落;氧化时间增加至50 h时,Cr_2O_3氧化层减薄,尖晶石状Cr、Fe大量剥落。同时内部大量形成Al、Ti内氧化物。综合考虑氧化行为对合金的影响,在满足合金均匀化要求的前提下,建议925合金的均匀化工艺为1160℃保温20 h。
The oxidation behavior of 925 alloy at the homogenization temperature of 1130 ~ 1190 ℃ was investigated by means of oxidation weight gain test, XRD, SEM and EDS. The results show that the complete homogenization of 925 alloy needs to be incubated at 1160 ℃ for more than 20 h. The oxide film formed in the homogenization is divided into three layers from the inside to the outside, which are the TiO 2 layer, the Cr 2 O 3 layer and the outer layer composed of TiO 2 and spinel Cr and Fe oxides. When the homogenization time exceeds 20 h, the Cr 2 O 3 layer begins to decrease and the spinel Cr and Fe oxides partially peel off. When the oxidation time is increased to 50 h, the Cr 2 O 3 oxide layer is thinned and the spinel Cr and Fe spall out largely. At the same time a large number of internal Al, Ti within the oxide. Considering the influence of the oxidation behavior on the alloy, under the premise of meeting the requirement of homogenization of the alloy, it is suggested that the homogenization process of the 925 alloy is heat preservation at 1160 ° C. for 20 h.