Scholarlink

<p>This study investigates the role of improper acid pickling in stress corrosion cracking (SCC) of S31603 U-tube heat exchangers. Through failure analysis of a leaked heat exchanger, it was found that excessive acid pickling during manufacturing induced intergranular corrosion grooves, which served as initiation sites for SCC. Comparative analysis of unused and failed tubes via scanning electron microscopy (SEM) revealed similar intergranular corrosion features on both, suggesting inherent defects from the pickling process. Energy-dispersive X-ray spectroscopy (EDX) identified sulfur and calcium deposits within these grooves, promoting pitting corrosion. Under residual and thermal stresses in the U-bend region, cracks propagated from these pits toward the outer wall, leading to through-wall failure. The results emphasize the criticality of controlled pickling parameters to mitigate SCC risks in austenitic stainless steel heat exchangers.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Effect of Pickling on Stress Corrosion Cracking of S31603 Heat Exchanger Tubes

  • 期刊论文

  • 发表日期：

    2025年5月6日

查看全文
  • Jian Zheng,
  • Jinlong Bo,
  • Lingling Ning,
  • Ranran Liu,
  • Chao Sun

摘要

This study investigates the role of improper acid pickling in stress corrosion cracking (SCC) of S31603 U-tube heat exchangers. Through failure analysis of a leaked heat exchanger, it was found that excessive acid pickling during manufacturing induced intergranular corrosion grooves, which served as initiation sites for SCC. Comparative analysis of unused and failed tubes via scanning electron microscopy (SEM) revealed similar intergranular corrosion features on both, suggesting inherent defects from the pickling process. Energy-dispersive X-ray spectroscopy (EDX) identified sulfur and calcium deposits within these grooves, promoting pitting corrosion. Under residual and thermal stresses in the U-bend region, cracks propagated from these pits toward the outer wall, leading to through-wall failure. The results emphasize the criticality of controlled pickling parameters to mitigate SCC risks in austenitic stainless steel heat exchangers.