| 摘要: |
| L360MCS针状铁素体管线钢焊接接头经HIC试验后热影响区产生大量的氢鼓泡.剥开氢鼓泡的上半部分,露出氢鼓泡的断口形貌.用扫描电镜和EDS分析氢鼓泡的上下两部分.结果表明,在绝大多数氢鼓泡的形核区存在偏聚的颗粒状Ca,Al元素夹杂物.分析认为H原子进入基体后,夹杂物周围的内应力和空位浓度升高是形成氢鼓泡裂纹形核空腔的主要原因,活性H原子在空腔内复合成H2分子导致空腔中活性H原子浓度低于基体中氢原子浓度是氢高压形成的重要原因. |
| 关键词: 夹杂 热影响区 L360MCS 氢鼓泡 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(50871122,50601029);高等学校博士学科点专项科研基金资助项目(20070425021) |
|
| Influence of cell segregation inclusion of alloying elements on initiation of hydrogen blistering in heat-affected zone of acicular ferrite steels |
|
ZHOU Chengshuang1, ZHENG Shuqi1, CHEN Changfeng1, CHEN Song2
|
|
1.Mechanical and Electrical Engineering Faculty, China University of Petroleum, Beijing 102249, China;2.Engineering Construction General Company of ZPEB SINOPEC, Puyang 457001, Henan, China
|
| Abstract: |
| After hydrogen-induced cracking test,many hydrogen blisters appeared in the heat-affected zone of the L360MCS acicular ferrite steels. The caps of the hydrogen blisters were torn off by sticking a layer of high silver brazing alloys and extending. Then the fracture surfaces of the blisters were analyzed by SEM and EDS. The cell segregation inclusion of alloying elements containing Ca and Al sulfides and oxides were observed in most of the initiating zones of the blisters. The results show that internal stress and increasing vacancy concentration are the main reason of forming void in the inclusion zone. The key reason how high hydrogen pressure forms is that the hydrogen atom concentration in the void is lower than that in the basal body due to combination from hydrogen atoms in the void. |
| Key words: inclusion heat-affected zone L360MCS steel hydrogen blistering |
