氮元素对高钛含铌钢裂纹影响的定量研究  

Quantitative effect of nitrogen on cracks in high Ti and Nb-bearing steels

作　　者：梅峰[1] 谢玉 徐国栋[1] MEI Feng;XIE Yu;XU Guodong(Steel-making Plant,Baoshan Iron&Steel Co.,Ltd.,Shanghai 200941,China;Research Institute,Baoshan Iron&Steel Co.,Ltd.,Shanghai 201999,China)

机构地区：[1]宝山钢铁股份有限公司炼钢厂,上海200941 [2]宝山钢铁股份有限公司中央研究院,上海201999

出　　处：《宝钢技术》2024年第2期40-44,共5页Baosteel Technology

摘　　要：应用试验、热力学计算及统计,定量研究了氮(N)对高钛(Ti)含铌(Nb)钢连铸横裂纹的影响,提出N控定量标准。结果表明:高钛含铌钢的高温塑性与氮化物形成具有强相关性;凝固末期TiN的析出影响第一脆性区,第二脆性区与Nb(C,N)的析出有关,温度区间为从Nb(C,N)析出到其析出速率开始缓和的温度,第三脆性区与铁素体或AlN析出有关,温度区间为从铁素体或AlN析出到渗碳体开始析出的温度。高钛含铌钢的N控瓶颈在于TiN在凝固末期的析出,根据Ti、N积建立控N标准,Ti、N积为4×10-5~7×10-5(%•%)。In this paper,the influence of nitrogen(N)on the occurrence of transverse cracks in high Ti and Nb-bearing steels was quantitatively studied by experimental analysis,thermodynamic calculation and statistical analysis,and N-controlled quantitative standards were proposed.It shows that the high-temperature plastic changes of the steel are strongly correlated with the formation of N compounds.The precipitation of TiN at the end of solidification affects the first brittle zone,then the second brittle zone is related to the precipitation of Nb(C,N)compounds,and the third brittle zone has a relationship with the transformation of ferrite and the precipitation of AlN compounds.The temperature range of the second brittle zone spans from the precipitation point of Nb(C,N)to the point where the precipitation rate of Nb(C,N)begins to ease.The temperature range of the third brittle zone spans from the beginning of the precipitation of ferrite or AlN to the point where cementite begins to precipitate.The N control bottleneck of steel types lies in the precipitation of TiN at the end of solidification.The N control standard is established according to the TiN product,and the TiN product is 4×10-5–7×10-5(%•%).

关 键 词：横裂纹 微合金钢 热力学计算 连铸 

分 类 号：TG142.33[一般工业技术—材料科学与工程]