论文部分内容阅读
以Fe-18Cr-30Ni为基础,添加不同含量的Al设计了4组新型奥氏体耐热钢。利用氧化质量增加法研究了4组新型奥氏体耐热钢在700、800和900℃下空气中的氧化行为,绘制了氧化动力学质量增加曲线,并利用XRD、SEM和EDS对氧化膜的表面形貌及结构进行了表征。结果表明,1~3号钢在900℃时均形成了较为致密的Al2O3内层氧化膜,合金表面生成的复合氧化膜由内到外依次为Al_2O_3、(Al_(0.9)Cr_(0.1))_2O_3、尖晶石氧化物Fe(Cr,Al)_2O_4;1号钢氧化过程中还形成了富(Cr,Fe)的混合氧化物,降低了Al_2O_3氧化膜的连续性;4号钢900℃并没有形成致密的Al_2O_3内层氧化膜,生成的复合氧化膜由内到外依次为(Al_(0.9)Cr_(0.1))_2O_3、尖晶石氧化物Fe(Cr,Al)_2O_4。
Based on Fe-18Cr-30Ni, four new types of austenitic heat-resistant steels were designed by adding different amounts of Al. The oxidation behavior of four groups of new austenitic heat-resistant steels in air at 700, 800 and 900 ℃ was studied by using the method of increasing the mass of oxidation. The oxidation kinetics of the steel was plotted and the oxidation kinetics was also plotted by XRD, SEM and EDS. Surface morphology and structure were characterized. The results show that all of the 1 ~ 3 steels form a dense Al2O3 inner oxide film at 900 ℃. The composite oxide films formed on the surface of the alloy are Al_2O_3, (Al_ (0.9) Cr_ (0.1)) _ 2O_3 , Spinel oxide Fe (Cr, Al) _2O_4. In the oxidation of No.1 steel, a mixed oxide rich in (Cr, Fe) was formed, which reduced the continuity of Al 2 O 3 oxide film. (Al_ (0.9) Cr_ (0.1)) _ 2O_3 and spinel oxide Fe (Cr, Al) _2O_4 were formed from the inside to the outside of the composite oxide film.