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研究了稀二元Al-Yb合金在不同时效温度下的析出强化行为。结果表明,在时效过程中析出了细小、弥散的L12结构Al3Yb相,时效析出所能达到的峰值硬度为400~416 MPa,各温度的峰值硬度比较接近。L12结构的Al3Yb析出相的粗化动力学遵循LSW理论,表明粗化由溶质原子扩散控制。当Al3Yb析出相的半径小于11 nm时其与基体保持共格关系,大于11 nm时开始出现半共格现象。当析出相的半径小于2 nm时,时效强化的机理是位错切割机制,大于2 nm时则主要为位错绕过的Orowan机制。
The precipitation strengthening behavior of dilute binary Al-Yb alloy at different aging temperatures was studied. The results show that the precipitated Al3Yb phase of L12 structure is precipitated during the aging process. The peak hardness of the Al3Yb phase precipitated by aging is 400 ~ 416 MPa. The peak hardness of each phase is relatively close. The coarsening kinetics of the Al 3 Yb precipitated phase of the L12 structure follows the LSW theory, indicating that coarsening is controlled by diffusion of solute atoms. When Al3Yb precipitates the radius of less than 11 nm, it maintains a coherent relationship with the matrix, and the semidegressive phenomenon begins to occur at more than 11 nm. When the radius of precipitated phase is less than 2 nm, the mechanism of aging strengthening is the dislocation cutting mechanism, while the Orowan mechanism mainly dislocations beyond 2 nm.