基于网格重构技术的空心铝型材挤压温度场分析

Analysis of the extrusion temperature field of aluminum hollow profiles based on the mesh reconstruction technology

采用焊合区网格重构技术,解决了大断面空心铝型材分流模挤压全过程的温度场模拟问题,分析了模孔出口处型材横断面温度分布情况,提出了合理的挤压速度范围。研究结果表明,挤压过程中型材横断面上最高与最低温度的位置并不固定,主要原因与模孔出口处不同位置的金属流速的变化有关。挤压初始阶段,型材横断面上圆弧半径较小端的金属流速较大,该部位的温度最高;随着挤压进行,型材横断面直边中部的金属流速逐渐增大,当挤压行程大于90 mm时,直边中部的金属流速大于圆弧半径较小端的金属流速,型材横断面最高温度出现在直边中部。根据6005A铝合金挤压生产中模孔出口处型材温度应为520℃~570℃的要求,该大断面空心型材合理的挤压速度为0.35 mm/s^1.05 mm/s。

Regarding the problem of the temperature field simulation in the whole process of divergent die extrusion of the aluminum hollow profile with large sections, it was solved by the mesh reconstruction technology of the welding zone. The temperature distribution on the cross section on the die outlet was analyzed, and the reasonable extrusion speed range was proposed. The results show that the unfixed positions of the highest and the lowest tempera- ture on the profile cross section are mainly related with the changing metal flow rates on dif- ferent positions of the die outlet. During the initial stage of extrusion, the metal flow rate was larger and the temperature was the highest on the end of the smaller arc radius. As extrusion continued, the metal flow rate on the center of the straight edge of the profile cross section in- creased. When the extrusion stroke was more than 90mm, the metal flow rate on the center of the straight edge was higher than that on the end of the smaller arc radius, and the highest temperature appeared on the middle of the straight edge. According to the requirement of the temperature range （520℃ -570℃ ） of the 6005A extrusion profile near the die outlet in extrusion production, the reasonable extrusion speed of the 6005 A aluminum hollow profile with the large cross section should range from 0.35 mm/s to 1.05 mm/s.