利用热重分析仪、扫描电镜和电子探针研究了含As或者Cu+As的C-Mn钢的高温氧化特性.1050℃氧化初期约500 s内,As钢和Cu-As钢为线性氧化阶段,随后转为抛物线氧化,两种钢的抛物线氧化速率均高于C-Mn钢.因氧化层分离,1150℃氧化增重小于1050℃氧化增重.钢中Cu和As的存在促进了固相Fe2Si O4层的生长.由于As在氧化层/基体界面的富集,1050℃氧化时,As钢中存在明显的条带状内部氧化粒子层;C-Mn钢中加入Cu和As后,其氧化层/基体界面变得崎岖不平,内部氧化粒子的数量随着氧化时间及氧化温度的增加而增加.1050℃氧化时氧化层/基体界面处Cu和As的富集程度高于1150℃氧化.
The high temperature oxidation characteristics of C- Mn steels containing As or Cu + As were investigated by thermo- gravimetry, scanning electron microscopy, and electron probe micro-analysis. It is shown that the oxidation kinetic curves at 1050 ℃ obey a linear law in the first 500 s and subsequently change to a parabolic law. The parabolic oxidation rates of the As and Cu- As steels are higher than that of the C-Mn steel. Due to separation of the scale from the matrix, the mass increment of the steels at 1150℃ is smaller than that at 1050℃. Cu and As in the steels could promote solid Fe2SiO4 layer growth. A significant internal oxidation particle layer is observed in the As steel because of As enrichment at the scale/steel interface at 1050 ℃. The interface is found to be uneven when Cu and As are added to the C-Mn steel, and the number of internal oxides increases with increasing oxidation time and temperature. The oxidation enrichment degree of Cu and As at the scale/steel interface at 1050 ℃ is higher than that at 1150℃.