摘要
某用户将IF钢板焊接成钢管用于制作家电冷凝管,在对焊管进行常规水压试验时,钢管表面局部出现点状缺陷的情况。使用金相显微镜、扫描电镜等手段,对点状缺陷进行化学成分分析及缺陷处微观组织、非金属夹杂物等检测,并对母材钢板进行力学性能及金相微观结构检测。结果表明,点状缺陷处有异常组织,异常组织含有Cr、Ni等合金元素,与基体化学成分不同。外来异物压入使焊管局部应力集中,水压试验时,从与基体结合薄弱的异物处产生打压漏点。为了避免此类表面缺陷的产生,应加强焊管整个生产过程、加工过程的质量监控,防止异物压入破坏基体的连续性,造成钢材质量下降。
The IF(Interstitial Free)steel plate is welded into steel pipe for manufacturing condenser pipe of household appliances by a user.There are local spot defects on the surface of steel pipe when it is subjected to conventional hydrostatic test.Such tests on chemical compositions,microstructure of defect and non-metallic inclusions of spot defects as well as mechanical properties and metallographic microstructure of the steel plate with base metal are carried out with such means as metalloscope and scanning electron microscope.The results showed that there were abnormal microstructures at the spot defects.The abnormal microstructures contain such alloying elements as Cr and Ni,which are different from the chemical compositions of matrix.When foreign matter is pressed into welded pipe,its local stress is concentrated.During hydrostatic test,the leak points of pressuring are at the foreign matter which is weakly combined with matrix.In order to avoid such surface defects,it is necessary to strengthen quality monitoring during the whole production and processing processes of welded pipe to prevent foreign matters from pressing into matrix to destroy its continuity so that the steel quality is reduced.
作者
寇沙沙
白雅琼
靳燕
Kou Sha-sha;Bai Ya-qiong;Jin Yan(Technical Center of Inner Mongolia Baotou Steel Union Co.,Ltd.,Baotou 014010,Inner Mongolia Autonomous Region,China)
出处
《包钢科技》
2024年第1期51-55,共5页
Science & Technology of Baotou Steel
关键词
焊管
点状缺陷
异物
welded pipe
spot defects
foreign matter
