通过制备不同尺寸的Ti_45.7Zr₃₃Ni_2.9Cu_5.9Be_12.5非晶复合材料样品, 研究了冷却速率和高径比对内生枝晶相增强钛基非晶复合材料力学性能的影响. 随着制备过程中冷却速率的降低, 非晶复合材料中枝晶相的尺寸逐渐增大, 同时枝晶相熟化的现象也趋于明显. 在力学性能方面表现为非晶复合材料的强度降低而塑性增强. 与以往非晶复合材料性能对高径比比较敏感所不同的是, 本工作中的Ti_45.7Zr₃₃Ni_2.9Cu_5.9Be_12.5非晶复合材料的力学性能对高径比的变化并不敏感, 原因在于晶态相的存在以及其中的形变诱发马氏体相变行为的发生对非晶复合材料内部应力分布的调节.

Amorphous alloy composite is designed to prevent rapid propagation of shear bands in amorphous phase by introducing the second crystalline phase, which can improve the plasticity of alloy. In situ formed amorphous alloy composites have attracted much interest due to excellent properties and extensive application prospect, especially the dendrite reinforced amorphous alloy composite with excellent tensile plasticity. Recent studies show that the plastic deformation behavior of amorphous alloy composite is not only related to the mechanical properties of the crystalline phase, such as elastic modulus, but also with the size, volume fraction and morphology of the crystalline phase. In addition, the mechanical properties, especially the plastic deformation ability, of amorphous alloys are closely related to topological morphology of the samples, such as aspect ratio. For the amorphous alloy composite, the relationship between mechanical properties and topological morphology of the samples are of interest. In this work, by adjusting preparation process and size of the samples, the effect of cooling rates and aspect ratios on the mechanical properties of Ti_45.7Zr₃₃Ni_2.9Cu_5.9Be_12.5 amorphous alloy composites were systematically studied. As decreasing the cooling rate during the preparation process, the sizes of dendrites in the amorphous alloy composites increases. And the crystalline phase presents evolution from branchlets to coarse dendrite. As the cooling rate decreases, strength of the composite decreases while plasticity increases. Moreover, different from the previous reports, the mechanical properties of amorphous alloy composite are not sensitive to the aspect ratio. It is attributed to the existing of the dendrites phase and deformation-induced phase transformation in the dendrites, which may adjust stress distribution of the amorphous alloy composites during deformation process.