采用快速凝固技术制备Zr₄₉Co₄₉Al₂、Zr₄₈Co₄₈Al₄、Zr₄₇Co₄₇Al₆合金棒，研究了合金的微观结构和力学性能，并分析了压缩时合金中裂纹萌生和扩展机理。结果表明：Zr₄₉Co₄₉Al₂合金、Zr₄₈Co₄₈Al₄合金和Zr₄₇Co₄₇Al₆合金的物相均为具有简单立方结构B2 ZrCo相，随着铝含量的增加，其（110）晶面间距增大且均略大于理论值；随着铝含量的增加，合金的弹性极限和屈服强度增大，塑性变形抗力降低，弹性能增大，在使用过程中的安全性变高；Zr₄₉Co₄₉Al₂合金和Zr₄₈Co₄₈Al₄合金压缩断口表面裂纹沿着应力加载方向扩展，晶界和晶粒变形吸收大量塑性功，导致合金具有较大的塑性变形，而Zr₄₇Co₄₇Al₆合金压缩断口表面未观察到裂缝扩展现象，晶界和晶粒近似同步变形，导致合金在塑性变形阶段呈现软化现象。

Zr₄₉Co₄₉Al₂, Zr₄₈Co₄₈Al₄ and Zr₄₇Co₄₇Al₆ alloy bars were prepared by rapid solidification technique. The microstructure and mechanical properties of the alloys were studied. The mechanism of crack initiation and propagation in the alloys in compression was discussed. The results show that the phase of Zr₄₉Co₄₉Al₂, Zr₄₈Co₄₈Al₄ and Zr₄₇Co₄₇Al₆ alloys was B2 ZrCo phase with simple cubic structure; the (110) crystal plane spacings increased with increasing aluminum content and were all slightly larger than the theoretical value. The elastic limit and yield strength of the alloys increased with increasing aluminum content, the plastic deformation resistance decreased, the elastic energy increased, and the safety in use increased. The cracks on compression fracture surface of Zr₄₉Co₄₉Al₂ and Zr₄₈Co₄₈Al₄ alloys propagated along the stress loading direction; the grain boundary deformation and grain deformation could absorb a lot of plastic work, resulting in large plastic deformation. No crack propagation was observed on the compression fracture surface of Zr₄₇Co₄₇Al₆ alloy, and the grain boundaries and grains almost deformed at the same time, leading to the softening of the alloy at the plastic deformation stage.