内冷式搅拌法制备A319半固态浆料工艺研究

Preparation of A319 Semi-solid Slurry by Internal Cooling Process

采用内冷式搅拌法制备了A319铝合金半固态浆料,研究了内冷块与铝合金液质量比、铝合金液温度、搅拌速度等工艺参数对半固态浆料显微组织的影响,分析了内冷式搅拌过程中半固态浆料的形成机理。结果表明,在内冷块与铝合金液质量比为5%、铝合金液温度为625℃、搅拌速度为1 100r/min时,可以制备出组织良好的半固态浆料,其中初生α-Al相平均晶粒尺寸和形状因子分别达到了59.7μm和0.74。提高内冷搅拌速度不仅能提高初生α-Al相的圆整度,还具有晶粒细化效应。

The semi-solid slurry of A319 aluminum alloy was prepared by internal cooling process.Effects of parameters,such as the mass ratio of internal cooling block to aluminum melt,the temperature of aluminum melt and the stirring speed,on the microstructure of semi-solid slurry were investigated.The forming mechanism of semi-solid slurry prepared by the internal cooling process was described.The results indicate that desirable globular primaryα-Al can be produced when the mass ratio of internal cooling block to aluminum melt is 5% with temperature of aluminum melt of 625 ℃ and stirring speed of1 100r/min,where the average diameter and shape factor of the primaryα-Al particles reach 59.7μm and 0.74,respectively.Roundness of the primary particles and grain refinement effects can be improved with the increase of stirring speed.