用慢应变速率法评定低合金钢焊接接头的应力腐蚀破裂

Stress Corrosion Cracking of Low Alloy Steels and Welded Joints in Sea Water

用慢应变速率法研究了４种低合金海洋用钢焊接接头在人工海水自腐蚀状态和阴极极化状态下的应力腐蚀行为．试验结果表明：在自腐蚀情况下，不会发生任何类型的应力腐蚀破裂，但在阴极极化状态下则可能由于过负的保护电位而产生氢脆型应力腐蚀破裂．提出了以氢脆临界转变电位ＥＨＥＣ作为评定环境氢脆敏感性的定量指标，用以代替析氢电位作为最大的阴极保护电位．

The stress corrosion cracking (SCC) of four types of marineused low alloy steels and welded joints were studied by the slow strain rate technique (SSRT) in artificial sea water. The experiments showed that under natural corrosion condition, there was no sign of SCC in the tested materials. Under the state of cathodic polarization, hydrogen embrittlement SCC would take place because of the excessive negative polarity of the applied protection potential. The concept of HEtransformation critical potential (EHEC) was used to replace of the “hydrogenseparateout potential” as the maximum cathodic protection potential.