摘要
分析了５５ＳｉＭｎＶＢ弹簧钢铸坯的凝固组织；测定了树枝晶二次枝晶臂间距；同时对铸中的非金属夹杂物作了金相形貌的观察与鉴定。结果表明，５５ＳｉＭｎＶＢ弹簧钢铸坯的凝固组织较疏松；二次枝晶臂间距较一般合金结构钢小（１００～２５０μｍ）；激冷层较簿（６～８ｍｍ）；中心等轴晶率低（２０％～２６％）；铸坯夹杂物含量偏高（０．７１％～１．２８％）。降低钢液过热度和提高凝固末端电磁搅拌强度，对减轻偏析、提高中心等轴晶率有一定的效果。
In this paper,the solidification structure of billet of spring steel 55SiMnVB was studied,and the spacing between secondary branch arms of dendritic crystal was measured.Besides,the metallographic morphology of nonmetallic inclu-sions wsa also observed.The resuIts reveals that the solidification structure of 55SiMnVB billet is loose,and the spacing between secondary branch crystal arms is from l00μm to 250μm, The thickness of chilling zone is 6～8mm,and the central e-quiaxed crystal ratio is 20%～26%。 The percentage of the nonmetallic inclusions is 0.71%～1.28%,which is higher than that of normal values。 Decreasing superheat temperature and increasing the intensity of magnetic stirring in the final stag of solid-ification are helpfuI to reduce the segregation and enhance the central equiaxed crys-tal ratio。
出处
《钢铁研究学报》
CAS
CSCD
北大核心
1995年第4期11-18,共8页
Journal of Iron and Steel Research
关键词
铸坯
弹簧钢
凝固组织
质量
熔炼
billet spring steel solidification structure quality
