稀土添加剂对N80套管钢低温渗铝层的影响  

Effects of Rare Earth Addition on the Microstructure and Properties of Low-temperature Aluminized Coating on Oil Casing Steel N80

作　　者：陈辉[1] 俞嘉诚[1] 王彦鹏[1] 黄敏[1] 王宇[1] 

机构地区：[1]台州学院物理与电子工程学院,浙江台州318000

出　　处：《热处理技术与装备》2015年第5期27-30,共4页Heat Treatment Technology and Equipment

基　　金：浙江省基金项目(LQ15ED10002)

摘　　要：为了提高N80套管钢的耐腐蚀性能,采用包埋温度为540℃,保温时间为4 h的低温渗铝工艺,通过在包埋粉料中添加不同种类及含量的稀土在N80套管钢表面制备渗铝层。借助扫描电镜、能谱仪和X射线衍射仪分析所得渗铝层的微观结构及物相组成;同时,通过模拟海水介质腐蚀试验测试了渗铝N80套管钢的电化学耐蚀性能。结果表明:在包埋粉料中添加稀土可以同时改善渗铝层的微观结构和相组成;添加稀土后所得渗铝层厚度较大,渗层连续均匀;稀土元素可以增强活性Al原子的扩散能力,改变渗层中的Al含量;与原始N80套管钢和未添加稀土渗铝处理后N80套管钢相比,在包埋粉料中添加3%Ce O2所得渗铝N80套管钢的自腐蚀电流密度最低。In order to improve the corrosion resistance of oil casing steel N80,low-temperature aluminizing coating was packed at 540 ℃ for 4 h with addition of different kind and content of rare earth in the pack powder. The microstructure and phase composition prepared aluminizing coating were analyzed by SEM,EDS and XRD. Electrochemical corrosion resistance of aluminized oil casing steel N80 was also tested by medium simulated sea water. The results show that the microstructure and phase composition of aluminizing coating can be improved by the addition of rare earth in the pack powder. Aluminizing coating obtained with the addition of rare earth is thicker and continuous uniform. The addition of rare earth can enhance diffusivity of active Al atom and change the concentration of Al in the aluminizing coating. Compare with original oil casing steel N80 and aluminized N80 without the addition of rare earth,aluminized oil casing steel N80 with the adding 3% Ce O2 in the pack powder shows the lowest self-corrosion current density.

关 键 词：N80套管钢 低温渗铝 耐蚀性 稀土 

分 类 号：TG156.86[金属学及工艺—热处理]