论文部分内容阅读
通过数值模拟及反挤压成形对半固态A357铝合金的密度及力学性能的不均匀性进行研究。结果表明:反挤压制件直壁部的相对密度最小,底部的最大。随着坯料高度的增加,转角处的相对密度需要更长的时间才能达到最高值;随着压力的增加,制件各部的相对密度均增加。模拟结果表明,制件的转角处的拉应力最大,该处产生热裂纹的可能性也最大。通过采用合适的坯料高度及压力,半固态挤压件能够获得细小、均匀的微观组织,且能达到优良的力学性能及硬度。
The density and mechanical inhomogeneity of semi-solid A357 aluminum alloy were studied by numerical simulation and reverse extrusion. The results show that the relative density of the straight wall part of the anti-extrusion parts is the smallest and the bottom part is the largest. As the billet height increases, the relative density at the corners takes longer to reach the maximum value; as the pressure increases, the relative densities of the parts increase. The simulation results show that the tensile stress at the corner of the workpiece is the largest, and the possibility of generating thermal cracks is also greatest here. Semi-solid extrusion enables the production of small, uniform microstructures with excellent mechanical properties and hardness through the use of suitable blanks height and pressure.