通过蠕变曲线的测定和TEM的形貌观察, 研究了AZ31镁合金在蠕变初期的变形特征及组织演化规律. 结果表明, 蠕变初期的变形特征是：大量形变产生的 a 位错在合金的基面和非基面滑移， a ＋c位错在锥面滑移。其中 a 位错通过位错分解反应可由一非基面交滑移至另一非基面。随蠕变进行, 高密度的形变位错发生动态回复，可进一步束集形成位错胞和位错墙。蠕变初始阶段, 在应力的作用下，适当取向的晶体发生孪生，并作为一种附加的变形机制而改善合金的韧性。
By means of the measurement of the creep curve and the observation of TEM, an investigation has been made into the deformation feature and microstructure evolution of AZ31 Mg--alloy in the initial creep at elevated temperature. The results show that the deformation feature during creep produced in the primary stage is that a great deal of $\langle a\rangle$ dislocation is activated on basal and non--basal planes, and $\langle a+c\rangle$ dislocation slips on pyramidal planes. $\langle a\rangle$ dislocation generated during creep may cross--slip from one of non--basal plane to another non--basal planes. As creep goes on, the dynamic recovery (DRV) may occur, and the dislocations are concentrated to form the dislocation cells or walls. Another feature observed during creep is that twinning occurs as an important deformation mechanism, leading to improvement of the alloy ductility.
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