锻压技术

大方坯往复轧制过程中内部空洞闭合行为的数值模拟

英文标题：Numerical simulation on internal void closure behavior in reciprocating rolling process for generous square billet

作者：杨清张立文张驰丁浩晨罗亚龙

单位：大连理工大学

分类号：TG142.1

出版年,卷(期):页码：2023,48(9):108-112

摘要：

空洞是方坯内不可避免的缺陷之一，由于大方坯尺寸较大，因此空洞闭合过程比较困难。通过Deform有限元软件建立带有空洞的轧件轧制过程热力耦合模型，并对空洞部分进行网格局部细划分，主要模拟研究往复横列式轧制过程中的空洞闭合行为。通过模拟直径范围为Φ9~Φ12 mm的空洞的演变情况发现，空洞越小，闭合越容易。此外，通过分析空洞在不同位置的演变规律可知，距离轧件表面越近，空洞闭合受轧制力的影响越大。当空洞接近表面时，空洞的闭合不仅受轧制力的影响，还受温度的影响，距离中心线102 mm的空洞在等效应变小于0.3时的闭合速度快，等效应变大于0.3之后，由于空洞周围的温度降低，空洞闭合速度减慢。减少转钢次数、增大轧制力、控制轧件温度有利于大方坯往复轧制过程中的空洞闭合。

The void is one of the unavoidable defects in the square billet. Due to the larger size of the generous square billet, the closing process of void is very difficult. Therefore, the thermal-mechanical coupling model of rolled parts with void in the rolling process was established by finite element software Deform, and the local subdivision of mesh for the void part was conducted to mainly simulate the void closure behavior in reciprocating transverse rolling process. By simulating the evolution conditions of the void with the diameter of Φ9-Φ12 mm, it is found that the smaller the void is, the easier it is to close. In addition, by analyzing the evolution laws of the void at different positions, it can be known that the closer to the surface of rolled parts, the greater the impact of rolling force on the void closure. When the void is close to the surface, the void closure is not only affected by the rolling force, but also by the temperature. The voids at a distance of 102 mm from the centerline are closed quickly when the equivalent strain is less than 0.3, and when the equivalent strain is greater than 0.3, the voids are closed slowly due to the decreasing of temperature around the voids. In summary, reducing the number of steel transfers, increasing the rolling force and controlling the temperature of rolled parts are beneficial to the void closure in the reciprocating rolling process of generous square bille.

基金项目：

中央高校基本科研业务费（DUT19JC26）

作者简介：杨清（1997-），女，硕士研究生 E-mail：3313409117@qq.com 通信作者：张立文（1962-），男，博士，教授 E-mail：commat@mail.dlut.edu.cn

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