摘要
采用金相组织检验分析等方法,分析了大规格82B拉拔劈裂脆断问题。结果表明:劈裂断口试样的中心处,由于锰、铬偏析而出现异常的马氏体组织,导致其变形与基体不一致,在拉拔过程中中心马氏体断裂成为裂纹源。断口附近表面存在结疤和擦伤等表面缺陷,中心马氏体和表面缺陷共同导致大规格82B拉拔劈裂脆断。通过优化合金元素锰、铬的成分含量,同时改善炼钢、轧制、拉拔等工艺,有效地降低了劈裂脆断的发生率。
The causes of drawing cleavage brittle fracture of large gauge high carbon steel 82B wire rod are analyzed by carrying out metallographic structure inspection and analysis.They are found out as the result of Mn,Cr central segregation causing formation of martensite in the centre of the wire rod,and the center martensite fracture becomes one of the sources of crack in the process of drawing because of the difference of deformation rate between the central part and the other area.There are some defects of scar and scratches near the fracture surface.It is manifested,through deeper analyzing,the main cause of drawing cleavage brittle fracture is the combined action of central martensite and surface defect.The incidence rate of cleavage brittle fracture defect has been reduced effectively through optimizing the content of Mn and Cr and improving the technics of steelmaking,rolling and drawing.
出处
《钢铁钒钛》
CAS
北大核心
2011年第3期82-86,共5页
Iron Steel Vanadium Titanium
关键词
高碳硬线
82B
拉拔
脆断
马氏体
high carbon wire rod
82B
drawing
brittle fracture
martensite
