The effect of Ta addition on mechanical properties of Zr-based bulk metallic glasses

• Published in: Intermetallics 2023-02, Vol.153, p.107779, Article 107779
• Main Authors: Xiong, Zusheng, Tao, Pingjun, Long, Ziyun, Huang, Zhengyang, Long, Kunhui, Zhu, Xuguang, Xu, Xi, Deng, Huanhuan, Lin, Haisheng, Li, Weiqiu
• Format: Article
• Language: English
• Subjects: Bulk metallic glasses; Mechanical properties; Microalloying; Nanoindentation
• ISSN: 0966-9795; 1879-0216
• DOI: 10.1016/j.intermet.2022.107779

Bulk metallic glasses (BMGs) exhibit poor room temperature plasticity, so improving their room temperature plasticity is important for amorphous alloys in engineering applications. In this paper, Zr60Cu(20-x)Al10Ni10Tax (x = 0, 1, 3, 5) bulk metallic glasses with 3 mm diameter rods were prepared by water-cooled copper mold suction casting, and investigated the effect of minor additions of Ta on the properties of Zr–Cu–Ni–Al alloys, especially on plasticity. The results show that the Zr-based alloys with a 3 mm diameter are amorphous. With the addition of Ta elements, the glass transition temperature hardly changed, the crystallization onset temperature increased from 747 K to 767 K, the width of the supercooled liquid phase zone increased from 49 K to 68 K, and the thermal stability of the alloy was improved. The room temperature uniaxial compression test found that with the increase of Ta content, the strength and plasticity of alloys showed a trend of first increasing and then decreasing, when the Ta content was 1 at.%, more interactive shear bands were observed on the side surface of the alloy after compression, while the fracture surface exhibited a complete vein pattern, and fracture strength and plasticity of samples reached to 1920 MPa and 13.8%, respectively. The results of nanoindentation tests indicated that when the Ta content was 1 at.%, the alloy exhibited the maximum indentation hardness and elastic modulus of 8.03 GPa and 101.48 GPa, respectively. It can be concluded that the right amount of Ta in Zr-based BMGs improves the mechanical properties, especially, the fracture strength, the plasticity, the indentation hardness, and the elastic modulus. •The maximum plasticity at room temperature of 13.8% when Ta is added at 1 at.%.•A reasonable amount of Ta addition can significantly improve the mechanical properties of Zr-based BMGs.•The change of atomic local stacking caused by Ta addition is closely related to the nanoidentation of BMGs.