含铬油套管钢的CO_2腐蚀点蚀特征研究

PITTING CHARACTERISTICS OF CO_2 CORROSION OF Cr-CONTAINING TUBULAR GOODS

在模拟油田CO2 腐蚀环境中 ,研究了不同含Cr量N80钢的点蚀特征。结果表明 ,普通N80钢CO2 腐蚀产物膜下会出现明显的点蚀现象 ,基体金属中加入Cr后 ,会有效抑制点蚀的发生 ;随着Cr含量增加 ,抑制作用增强。 1%Cr的N80钢点蚀坑大小明显小于普通N80钢 ,而 4%～ 5 %CrN80钢则呈均匀腐蚀形态 。

Pitting behavior of N80 steel with different Cr contents was studied in simulating environment containing CO 2. The results demonstrated that pitting occurred beneath the CO 2 corrosion scale of N80 steel, while adding Cr to the base metal, pitting was prohibited effectively and the size of pits of 1%Cr-containing N80 steel was much smaller than ordinary N80 steel, and N80 steel containing 4%～5% Cr was only corroded uniformly, no pitting occurred.