三辊辊模拉拔的变形力学研究

THE MECHANICS OF DEFORMATION IN WIRE DRAWING THROUGH THREE-ROLLER DIES

本文对三辊辊模拉拔的变形力学问题进行了研究。通过引入数值解析法对辊模拉拔的辊拉力和辊压力进行了理论解析。同时,对变形区内的应力应变分布特征作了较详细的分析。现论解析和实验结果表明: 1.实验与理论解析的结果一致。 2.拉拔条件对辊拉力和辊压力有影响,其中,后张力影响较强,润滑条件影响较弱。辊模拉拔辊拉力明显小于固定辊模拉拔。 3.辊模拉拔的宽展受拉拔条件影响,自由辊模拉拔宽展大于固定辊模拉拔。 4.辊模拉拔变形区内的应力应变分布特征完全不同于固定辊模拉拔,而倾向于轧制过程。 5.进行了三辊辊模拉拔螺纹钢筋的实验,拉出了φ4.0mm螺纹钢筋。

The purpose of this paper is to make clear the mechanism of deformation in wire drawing through three roller dies. Having introduced the numerical method, the drawing process, including drawing force and roll force, has been theoretically analyzed. In addition, the distribution characteris tics of mean stresses and mean strains in the deformation zone have been investigated. The results are as follows.1. The experimental results were in good agreement with the theoretical analysis.2. Drawing condition affects drawing force and roll force, in which the effect of back pull is large but the effect of lubrication is small. Drawing force under free roller dies drawing is much smaller than that under fixed rolls drawing.3. The rate of breadth spread is affected by drawing condition. The rate of breadth spread under free roller dies drawing is larger than that under fixed rolls drawing.4. The distribution of stresses and strains in the deformation zone under roller dies drawing is different from that under fixed rolls drawing, but tends towards rolling.5. The (?)4.0 mm ribbed bars have been drawn through three roller dies.