摘要
采用蛇形通道浇注技术制备半固态7075铝合金浆料，研究浇注温度和弯道数量对半固态7075铝合金浆料微观组织的影响。结果表明：当浇注温度为680-700℃时，可以制备出质量较好的半固态7075铝合金浆料；在相同浇注温度条件下，随着弯道数量的增加，初生α（Al）的平均晶粒尺寸减小，形状因子提高。在浇注制备半固态7075铝合金浆料过程中，合金熔体在具有一定弧度且封闭的蛇形弯道内流动并多次改变流动方向，具有类似“搅拌”的功能，使得初生晶核逐渐演变为球形或近球形晶粒。
The semi-solid slurry of 7075 aluminum alloy was prepared by a serpentine pouring channel （SCP）. Influences of pouring temperature and the number of turns on the microstructure of semi-solid 7075 alloy slurry were investigated. The results demonstrated that the semi-solid 7075 aluminum alloy slurry with satisfied quality could be generated by a serpentine pouring channel when the pouring temperature was in the range of 680-700 ℃. At a given pouring temperature, the equivalent size of the primaryα（Al） grains decreased and the shape factor increased with the increase of the number of turns. During the slurry preparation of semi-solid 7075 aluminum alloy, the flow direction of alloy melt changed many times when it flowed in a curved and closed serpentine channel. With the effect of“stirring”in it , the primary nuclei gradually evolved into spherical and near-spherical grains.
基金
Project (2011CB606302-1) supported by the National Basic Research Program of China
