摘要
利用扫描电镜观察、化学成分分析、金相检验和残余应力测试等方法,从断口形貌、材料成分、微观组织等角度系统分析了出现大量裂纹的板式换热器板片样品。结果表明:换热器板片腐蚀孔与裂纹均源于冷却水侧,其失效的主要原因是密封槽存在较高的残余应力、板片长期处在含有较多氯离子和硫离子的循环介质中发生了应力腐蚀破裂所致。
The plate samples of plate heat exchanger with a large number of cracking was systematically analyzed by using SEM, chemical composition analysis, metallographic examination and residual stress test in fracture surface, material composition and microstructure. The results indicate that corrosion pits and cracking are originated in cooling water side of plate heat exchanger, and high residual stress in seal groove, working environment of cycle medium contained large number of cycle medium contained large number of Cl^- and S^2- are the key factors of the stress corrosion cracking. The SCC leads to plate failure.
出处
《压力容器》
北大核心
2011年第9期42-46,共5页
Pressure Vessel Technology
