介质温度对35CrMo钢在CO_2环境下腐蚀的影响及其机理  

Influence of medium temperature on mechanism of 35CrMo steel corrosion in CO_2 environment

作　　者：张家林[1,2] 李春福[1] 张雷 张凤春[1] 文平[1] 

机构地区：[1]西南石油大学油气藏地质与开发工程国家重点试验室,四川成都610500 [2]西南石油大学材料科学与工程学院,四川成都610500 [3]中国石油集团工程设计有限责任公司北京分公司,北京100085

出　　处：《金属热处理》2015年第2期195-200,共6页Heat Treatment of Metals

基　　金：国家高技术研究发展计划(863计划)(2006AA06A105)

摘　　要：为了研究35CrMo钢钻采工具的井下腐蚀行为,模拟了油田地层水环境,通过腐蚀质量损失、交流阻抗等试验方法,测试了该钢材在30、60、80和100℃等不同温度下的耐腐蚀性,用SEM、EDS、XRD手段对腐蚀产物膜的形貌、成分、结构进行了分析,对钢材在不同温度下的腐蚀机理进行探讨。结果表明,温度可以改变35CrMo钢的腐蚀产物膜结构,在30~60℃温度范围内,随温度升高,腐蚀速率变大,35CrMo钢表面的腐蚀产物膜为片层状、较薄且结构松散,主要成分为FeCO3和Cr（OH）3;在60~100℃温度范围内,随温度升高,腐蚀产物膜致密性变好,晶粒变细,腐蚀速率变小,腐蚀产物膜上层为晶体,主要成分为FeCO3,下层为片状生成物,成分为Cr（OH）3。Corrosion behavior of 35 CrMo steel for downhole drilling tools was investigated through simulating formation water environment in an oilfield under different temperatures of 30, 60, 80, 100 ℃. Corrosion mass loss test and alternating-current impedance test were carried out, the morphology, chemical composition and phase structure of corrosion product films were analyzed by means of SEM, EDS and XRD, and its corrosion mechanism at different temperature was discussed. The results show that the medium temperature can affect the structure of corrosion product film, the corrosion rate increases with the temperature in the range of 30450 ℃ increasing, and the main component of corrosion product is FeCO3and Cr（OH）3 which is lamellar, thin and loose. With the temperature in the range of 60-100 ℃ increasing, the corrosion product film gets more compact, its grain size becomes smaller and the corrosion rate decreases, and the upper layer of corrosion product film is crystal, mainly composed of FeCO3, and the lower layer is a sheet-like product composed of Cr（OH） 3-

关 键 词：35CRMO钢 介质温度 腐蚀机理 

分 类 号：TG178[金属学及工艺—金属表面处理]