水平连铸铅黄铜铸锭凝固组织的分析和控制

以废杂铜为原材料水平连铸生产的铅黄铜铸锭为研究对象,对两种不同直径铸锭的宏观组织及微观组织进行了研究。结果表明,105mm铸锭的组织分布比较正常,晶粒比较细小,横断面未发现明显柱状晶组织,以等轴晶为主。150mm铸锭的组织区域出现混乱,横断面中发现柱状晶组织,粗等轴晶区域比较靠近铸锭的下部。铅存在于等轴晶的晶界处,铅质点圆滑、细小。通过分析认为,二次冷却不匀和结晶器冷却能力在圆周方向上出现的偏差是造成凝固组织发生改变的主要原因。采用环形冷却装置对铸锭进行二次冷却和降低拉坯温度后,发现铸锭凝固组织得到了改善。

Analysis and Control of Solidification Structure in Horizontal Continuous Casting Pb Brass Ingot

Macro-structure and microstructure of horizontal continuous Pb brass with two diameters produced with copper scraps as raw materials were observed by OM (optical microscope) and SEM (scanning electron microscope). The results reveal that microstructure of the ingot with 105 mm in diameter is mainly composed of equiaxed grain with fine size, and absence of apparent columnar grain at cross section can be observed, while microstructure of the ingot with 150 mm in diameters exhibits turbulent, and presence of c...