Cooling-rate-dependent microstructure and mechanical properties of a CuZrAlAg alloy

Abstract

A Cu₃₆Zr₄₈Al₈Ag₈ alloy rod with a diameter of 10 mm was fabricated using a copper-mould suction casting method. Structural characterization revealed that the rod has different microstructures along the casting direction, including a complete amorphous structure and an amorphous/crystalline composite structure with different amount of B2 CuZr phase. Nanoindentation tests showed that the hardness and the elastic modulus of the crystalline phase are lower than those of the amorphous matrix. The hardness and the elastic modulus of the amorphous matrix decrease with decreasing crystalline proportion of the alloy, while the Vickers hardness of the alloy increases with a reduction in the crystalline proportion.

Keywords:

• CuZrAlAg alloy
• amorphous
• nanocrystalline
• mechanical properties
• nanoindentation

Additional information

Funding

Funding. This project is supported by the National Natural Science Foundation of China [grant number 51328101, 51301207], the China Postdoctoral Science Foundation [grant number 2013M531806], the China Postdoctoral International Exchange Program, Hunan Provincial Natural Science Foundation of China [grant number 11JJ2024] and the Fundamental Research Funds for Central Universities [grant number 2011JQ021].