6201合金管材连续流变扩展挤压成形过程的数值模拟和实验研究

数值模拟和实验研究了6201合金管材连续流变扩展挤压成形过程中的温度场分布和熔体流动规律.结果表明,在连续流变扩展挤压6201合金管材过程中,辊-靴型腔中的合金等温线向轧辊侧偏移,随着浇注温度的升高半固态区间逐渐下移;在辊-靴型腔中合金熔体服从牛顿流体的层流运动规律,从工作辊表面向靴表面速度依次递减,在靴表面速度为0 ...

Simulation and Experimental Research on Continuous Extending Rheo-extrusion Process for Producing 6201 Alloy Tube

Simulation and experimental investigation of temperature field distribution and metal flow behavior of 6201 alloy were conducted in this paper. The results show that during extending rheo– extrusion process, the isothermal lines of alloy deviate to the roll side in the roll–shoe gap, and semisolid region moves down little by little with the decrease of pouring temperature. Alloy melt in the roll–shoe gap flows by Newton laminar fluid law, and the velocity decreases gradually from the roll surface to the shoe surface where the velocity reaches 0 m·s⁻¹. Alloy melt fills the extending cavity with a radial pattern layer by layer, and then it splits and concentrates. It also exhibits homogenous laminar flow. The flow velocity is maximal at the centers of the mould and the branch holes, and decreases gradually to the side wall. The flow lines on the cross section of the tube corresponding with the branch holes center and the wielding region are dense. But there is a transitional region where the flow line is sparse. The proper pouring temperature for producing 6201 alloy tube is between 750^oC  and 780^oC.