Investigation of separation phenomenon in high-toughness X70 thick-walled linepipe steel  

作　　者：DING Jianhua LIANG Xiaojun JIAO Sihai 

机构地区：[1]Research Institute,Baoshan Iron & Steel Co.,Ltd.

出　　处：《Baosteel Technical Research》2015年第3期35-40,共6页宝钢技术研究（英文版）

摘　　要：Separation is a commonly observed phenomenon during drop weight tear testing in high-toughness linepipe steels. Severe separation is harmful because it may cause fracturing or bursting of pipes. In this study, a quantitative measurement of separation was proposed, and using this new method, a relationship between the separation and microstructure was determined and discussed. The microstructures observed using optical and scanning electron microscopy revealed that the separation was related to the mixed ferfitic and bainitic microstructures, or rather,it was related to the carbon enrichment in bainite.Separation is a commonly observed phenomenon during drop weight tear testing in high-toughness linepipe steels. Severe separation is harmful because it may cause fracturing or bursting of pipes. In this study, a quantitative measurement of separation was proposed, and using this new method, a relationship between the separation and microstructure was determined and discussed. The microstructures observed using optical and scanning electron microscopy revealed that the separation was related to the mixed ferfitic and bainitic microstructures, or rather,it was related to the carbon enrichment in bainite.

关 键 词：linepipe steel DWTT SEPARATION BAINITE thermomechanical processing cleavage fracture 

分 类 号：TG142.1[一般工业技术—材料科学与工程]