APIX56钢在含H2S的海洋大气中的应力腐蚀开裂  

STRESS CORROSION CRACKING OF X56 GRADE PIPELINE STEEL IN ATMOSPHERIC ENVIRONMENT CONTAINING H_2S

作　　者：郑传波[1,2] 黄彦良[1] 霍春勇[3] 于青[1,2] 朱永艳[1,2] 

机构地区：[1]中国科学院海洋研究所,青岛266071 [2]中国科学院研究生院,北京100039 [3]中国石油天然气总公司石油管材研究所,西安710065

出　　处：《中国腐蚀与防护学报》2009年第1期19-23,共5页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金项目(40576049),中国科学院知识;创新工程重要方向项目(KZCX2一Yw一210)

摘　　要：采用慢应变速率拉伸及Devnathan-Stachurski双电解池技术研究了X56钢在模拟海洋大气环境中形变及H_2S含量对其应力腐蚀开裂及氢渗透行为的影响。结果表明,在H_2S含量相同时,拉伸速率越小,试样断裂延伸率越小。在相同拉伸速率下,随着H_2S含量增大,试样断裂延伸率减小,扫描电镜微观分析(SEM)表明,其断裂特征由塑性断裂逐渐转变为脆性断裂。电化学渗氢实验表明,随着H_2S含量的增大,第一干湿循环氢渗透电流并不单调增大,H_2S对氢渗透电流的作用由H_2S的表面覆盖度和腐蚀产物膜来共同控制。从多个干湿循环来看,H_2S可增大氢渗透电流,材料的渗氢加剧,脆性增大。Susceptibility to SCC of X56 grade pipeline steel was investigated by slow strain rate test （SSRT） and Devnathan-Stachurski double electrolytic cell in atmospheric environment containing H2S. The results showed that the fracture strain decreased while the strain rate decreased in the same H2S concentration environment. And the fracture strain decreased with increasing the concentration of H2S at the same strain rate 6.67× 10^-7 s^-1. The SEM fractographs of the specimens also showed that the susceptibility to stress corrosion cracking （SCC） increased. The hydrogen permeation test showed that hydrogen permeation current did not increase with increasing the concentration of H2S in the first wet-dry cycle because of the formation of product film. The longer the experiment time, the more the hydrogen atom permeated through the specimen. This trend partially attribute to the surface coverage ratio （θ） of H2S and the corrosion product film.

关 键 词：H2S应力腐蚀开裂敏感性氢脆大气腐蚀 

分 类 号：P734[天文地球—海洋化学] P755.3[天文地球—海洋科学]