1.The penpoint fracture is main due to non-metallic inclusions and center segregation.
笔尖状断裂主要由非金属夹杂和中心偏析造成;
2.penpoint fracture and breaking on the early course of drawing are caused by shrinkage void inside the rod;
断口呈笔尖状,在拉拔早期发生断裂是由于内部存在缩孔缺陷所致;