MODELING OF WIRE WITH FLAW IN MULTI-DRAWING AND OPTIMIZATION OF DRAWING TECHNIQUE
含缺陷钢丝多道次拉拔模拟及工艺参数优化

Numerical model of the wire with defect in the process of multi-drawing is built based on finite element method and fracture mechanics, and the effects of parameters (draft reduction, die angle and cracking) on the wire drawing are analyzed. It is concluded that the effective method to reduce the rate of broken rods is: choose the best parameters in multi-drawing process about the draft reduction and die angle; control the length of crack by using nondestructive examination to improve the quality of the finished product. The results show that values of $J$-integral and COD increase with the increasing length of crack in the same die angle; the best condition diameter increases with the increasing die angle in the same length of crack; the best die angle is in the range of 4$^\circ \sim 8^\circ$. The above findings can be used to improve wire drawing technique and the quality of wire.