2618铝合金半固态压缩变形特性

COMPRESSION BEHAVIOR OF 2618 ALUMINUM ALLOY IN SEMI SOLID STATE

采用常规铸造和液相线铸造的２６１８ 铝合金在Ｇｌｅｅｂｌｅ － １５００ 型热学－ 力学模拟试验机上在不同变形温度和变形速率下进行半固态压缩， 变形温度为４９０ ～６００ ℃， 变形速率为５ ×１０ － ３ ～５ ×１０ － １ ｓ－ １ 。结果表明， 常规铸造组织、液相线铸造组织半固态压缩变形抗力均小于固态压缩变形抗力，并且液相线铸造获得的细小、等轴、非枝晶组织在半固态压缩时的变形抗力小于常规铸造枝晶组织的变形抗力。

aluminum alloy attained by conventional casting and liquidus casting was compressed in semi solid at different deformation temperatures from 490～600 ℃ and different deformation rates ranging from 5×10 -3 to 5×10 -1 s -1 by means of Gleeble 1500 thermal mechanical simulator . The results showed that the resistance to deformation of compression in semi solid state is lower than that in solid state, for both conventional casting and liquidus casting structures; the resistance to deformation of the fine, equiaxed and non dendritic grains of primary microstructure attained by liquidus casting in semi solid state is remarkably lower than that of conventional casting dendritic microstructure; the formability of liquidus cast structure is better than that of the conventional cast structure.