Aging process of as-cast 6066 aluminum alloys were optimized using a micro hardness change curve.The second phases in the alloy were observed by SEM after the heat treatment and hot extrusion.The mechanical properties of the alloy were measured after the heat treatment and hot extrusion.The results show that the best aging process of the alloy is heating at 175 ℃ for 4 h,and the heat treatment makes the silicon dissolve and the continuous AlFeSi phase,πphase and W phase in the grain boundaries transform into acicular β-FeSiAl5 in the as-cast alloys.The second phases after hot extrusion become granular AlFeSi phase.Besides,after the heat treatment strength of the alloy is improved,with its ductility not being improved.After extrusion and T6 treatment the tensile strength of the alloy containing scandium reaches as high as 440 .8 MPa,and its elongation is more than 1 4%.%利用显微硬度变化曲线对铸态6066铝合金的时效工艺进行了优化。利用扫描电镜对热处理、热挤压后合金的第二相形貌变化进行了观察。测定了热处理、热挤压后合金的力学性能。结果表明，合金的最佳时效处理工艺为175℃×4 h，热处理使铸态合金中 Si 单质溶解，沿晶界分布的连续AlFeSi相、π相和W相转变为针状β-FeSiAl5相。热挤压后第二相转变为颗粒状AlFeSi 相。热处理后合金的强度提高，塑性未有改善。挤压后T6状态含钪铝合金的抗拉强度达到440．8 MPa，断后伸长率大于14％。
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