The experimental results showed that the microstructure of low Nb content steel is composed of polygon ferrite and some amount of lath bainitic ferrite and few amount of pearlite.
结果表明,低铌钢热处理后组织为多边形铁素体加少量板条贝氏体铁素体加极少量珠光体,随着铌含量增加,试验钢组织中板条贝氏体铁素体含量明显增加,且组织细化;同时随着铌含量的增加强度提高,中高铌试验钢的屈服强度可达400 MPa,且屈强比较小(<0。
From the results of the analysis on chemical composition, microstructure and morphology of crack fracture of the raw tube, it was observed that cracks were mainly related to the ferrite band and chain-like inclusion of titanium nitride present in the raw tube.
奥氏体不锈钢管坯在切割过程中发生分层开裂,对该管坯进行化学成分、微观组织及裂纹断口形貌的分析表明,管坯的开裂主要与条状铁素体和链状氮化钛夹杂有关。