【摘要】 文章研究了对Mg-9Gd-4Y-0.6Zr合金在时效过程中的微观组织。在225℃时效初期硬度缓慢上升,之后硬度急剧上升,24 h出现了明显的时效硬化峰,然后硬度开始下降。微观结构的分析结果表明,在初期(2 h)产生了大量弥散分布的具有DO19结构的β″,而在峰值时(24 h)出现具有bco的β′,在持续时效(384 h)时出现亚稳相β1,而在后来的长时间时效(1 000 h)时出现β1在原位转变的平衡相β。更多还原

【Abstract】 Strengthening precipitate phases and hardness in a Mg-9Gd-4Y-0.6Zr alloy,aged at 225 ℃,have been investigated using transmission electron microscopy(TEM).It shows that the value of hardness increases quickly after 2 h.The specimens exhibit the peak-aged hardness at 24 h,then decrease.The microstructure of TEM reveal that a lot of fine precipitates of β″ phase with DO19 crystal structure appear at the first age(2 h),then β′ phase with bco crystal structure(24 h),then β1(384 h),and the last,β(1 000 h).更多还原