【摘要】 研究了不同工艺均匀化退火过程中Al-Zn-Mg-Cu-Zr合金中组织、低熔点结晶相和弥散相的演变规律。结果表明：铸态Al-Zn-Mg-Cu高强铝合金中主要结晶相为AlMgZnCu四元相，均匀化退火后该相部分消除。均匀化退火过程中，随着温度的提高及时间的延长，合金中的非平衡结晶相逐渐溶解，未溶结晶相的体积分数降低。弥散相Al₃Zr的尺寸及分布取决于均匀化退火过程中的升温速度，在缓慢升温条件下，弥散相Al₃Zr的尺寸细小，分布比较弥散，密度高，合金的电导率最低；随着升温速度提高，Al₃Zr相的析出数量减少，尺寸增加，析出相的密度降低，合金的电导率升高。二段均匀化退火后，弥散相Al₃Zr的尺寸更加细小，密度更高，平均直径为15 nm,密度为1.27×10¹⁵/cm³。更多还原

【Abstract】 The effect of homogenization annealing process on the microstructure, low melting point crystalline phase and dispersoids（Al₃Zr） in a high-strength Al-Zn-Mg-Cu aluminum alloy was investigated. The results show that the constituent in the as-cast high-strength aluminum alloy is mainly AlZnMgCu type compound which is partly eliminated after homogenization. With the increasing of temperature and time, the non-equilibrium crystalline phase is dissolved and the volume fraction of the undissolved crystalline phase is decreased. The size and the distribution of the dispersoid particles obtained depends on the heat-up rate during the homogenization annealing process. At low heating rate, dispersed phase Al₃Zr has a small size, relatively dispersed distribution, high density, and the alloy has the lowest conductivity. With the increase of heating rate, the quantity of precipitated Al₃Zr phase decreases, the size increases, the density of precipitated phase decreases, and the electrical conductivity of the alloy increases. After the two-stage homogenization annealing, the dispersed phase Al₃Zr is finer and the density is higher. The average diameter is 15 nm and the density is 1.27×10¹⁵/cm³.更多还原