论文部分内容阅读
采用数值模拟与工艺实验相结合,研究了挤压轮转速对铝锶合金连续挤压成形过程和产品组织性能的影响。通过数值模拟分析了不同转速下坯料的温度、速度和等效应变分布情况以及模具的温度分布规律并利用金相观察和拉伸试验分析了不同转速下实际连续挤压产品的组织性能。结果表明,铝锶合金在连续挤压过程中,坯料进入腔体后,温度开始升高,最高温度和最大速度出现在模具出口处;最大等效应变出现在直角弯曲处。当挤压轮转速由4r·min~(-1)增加到7r·min~(-1)时,腔体内的坯料最高温度由460℃升高到514℃,模具出口处的温度由490℃升高到527℃;产品中Al4Sr相形态由块状变成颗粒状,尺寸减小;抗拉强度由98.7MPa上升到106.9MPa,伸长率变化不大,维持在约11%。
The effects of extrusion wheel rotation speed on the extrusion process and the microstructure and properties of Al-strontium alloy were investigated by numerical simulation and experiment. The temperature, velocity and equivalent strain distribution of the blank at different rotation speeds and the temperature distribution of the die were analyzed by numerical simulation. The microstructure and properties of the actual continuous extrusion products at different rotation speeds were analyzed by metallographic observation and tensile test. The results show that during the continuous extrusion of aluminum-strontium alloy, the temperature begins to increase after the billet enters the cavity, and the maximum temperature and the maximum velocity appear at the exit of the die. The maximum equivalent strain appears at the right-angle bend. When the speed of extrusion wheel was increased from 4r · min -1 to 7r · min -1, the maximum temperature of the billet in the cavity increased from 460 ℃ to 514 ℃. The outlet temperature of the die increased from 490 ℃ Up to 527 ℃. The morphology of Al4Sr phase in the product changed from massive to granular and the size decreased. Tensile strength increased from 98.7MPa to 106.9MPa with little change in elongation at about 11%.