含硼钢板坯角横裂产生原因及控制研究  

Formation and Control of Transverse Corner Cracks in Boron Steel Slab

作　　者：刘国梁[1] 季晨曦[1] 倪有金[2] 胡卫东[2] 张颖华[2] 包春林[1] 

机构地区：[1]首钢技术研究院薄板所,北京100043 [2]首钢迁安钢铁有限责任公司,河北迁安064404

出　　处：《钢铁钒钛》2013年第4期94-98,103,共6页Iron Steel Vanadium Titanium

摘　　要：利用透射电镜、扫描电镜和金相分析等对含硼钢板坯边部角横裂进行了观察,并对铸坯角横裂产生原因进行了分析。研究表明:板坯角部过冷导致奥氏体晶界细小的BN、AlN析出,加剧了连铸坯对裂纹的敏感性,微小裂纹首先在铸坯较高温度区沿振痕产生,然后微小的裂纹经过弯曲矫直扩展延长形成铸坯角横裂。还对SS400B的热塑性进行了研究,根据研究结果提出了采用"强冷"预防铸坯角横裂的措施。Transverse corner cracks in boron steel were studied through TEM, SEM and optical micro scope analyses, and the formation reasons of the cracks were analyzed. The results indicates that BN and AIN precipitate around austenitic grain boundaries due to undercooling at the corner, which aggravates the cracks during continuous casting. Tiny cracks firstly appear along vibration marks at higher tempera ture zone of the continuously cast slab, then extend to transverse corner cracks during bending and straightening process. Moreover, hightemperature mechanical properties of SS400B was investigated, and based on the results, ＂intensified cooling＂ was put forward to prevent the formation of transverse cor ner cracks in slabs.

关 键 词：含硼钢 角横裂 板坯 高温力学性能 析出相 

分 类 号：TG245[金属学及工艺—铸造]