X90管线钢焊接接头耐腐蚀性能研究

采用金属浸泡腐蚀试验、电化学腐蚀试验研究不同浓度或pH的HCl、NaOH、NaCl溶液对X90管线钢焊接接头(SMAW、GMAW、SAW)耐腐蚀性能的影响。结果表明:三种焊接接头的腐蚀速率随溶液浓度增加而增加,其中焊接接头对碱性环境耐蚀性较好,耐酸、盐类腐蚀性能较差,在较低浓度或pH下腐蚀接近轻度级别,SMAW焊接接头在pH=1的HCl溶液和5%的NaCl溶液中腐蚀达到重度级别。电化学腐蚀试验表明,SMAW试样自腐蚀电流最高,阻抗最低,三种焊接接头腐蚀均为重度级别,因此在强电解质溶液中建议采取保护措施。

Study on corrosion resistance of welded joint of X90 pipeline steel

Use metal immersion corrosion test,electrochemical corrosion test to study the influence of different concentration or pH of HCl,NaOH,NaCl solution on corrosion resistance of X90 pipeline welded joints (SMAW,GMAW,SAW).The results show that,the corrosion rate of three kinds of welded joints increases with increasing concentration,alkaline environment in which the welded joints ofgood corrosion resistance,acid and salt corrosion is poor,at lower concentrations or pH close under corrosive light degree level,SMAW welding joint at pH=1 HCl solution and 5％ NaCl solution corrosion could reach severe level.Electrochemical corrosion tests show that SMAW sample corrosion current highest,lowest impedance,three welded joints corrosion are severe level,so suggest protective measures in strong electrolyte solutions.