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通过铜模铸造法制备了最大厚度达5mm的板状(Zr_70Ni_10Cu_20)_82-Ta_8Al_10非晶复合材料,不同的冷却速度使制备的不同厚度的非晶复合材料含有不同的延性相和脆性相.延性Ta固溶体粒子的存在可以促使多重剪切带的萌生,导致剪切带分叉、阻碍剪切带或者裂纹的扩展来提高材料的塑性;而延性Ta固溶体周围脆性相的析出减弱了固溶体与非晶基体的界面结合强度,进而降低了Ta固溶体提高塑性的能力,同时非晶基体中的脆性相起到了促使裂纹形核、引起低应力脆断的发生,随着脆性相数量的增加,试样的断裂模式也由失稳屈曲-剪切模式向劈裂模式转变.
The amorphous (Zr_70Ni_10Cu_20) _82-Ta_8Al_10 amorphous composites with maximum thickness up to 5mm were prepared by copper mold casting. The different cooling rates resulted in different thicknesses of amorphous composites with different ductile and brittle phases. The existence of solid solution particles can promote the initiation of multiple shear bands, leading to the bifurcation of the shear bands, hindering the extension of the shear bands or cracks to improve the plasticity of the material. The precipitation of brittle phase around the ductile Ta solid solution weakens the solid solution and the amorphous matrix , And then the ability of Ta solid solution to improve ductility was reduced. At the same time, the brittle phase in the amorphous matrix played a role of promoting the nucleation of cracks and causing the occurrence of low-stress brittle fracture. With the increase of the number of brittle phases, The mode also changes from buckling-shear mode to splitting mode.