Spark Plasma Sintering: A Useful Process to Produce Bulk Metallic Glasses and Composites Using a Commercial Zr-Cu-Al-Nb Amorphous Powder

摘要

Bulk metallic glasses are attractive materials. However, most of them are obtained by casting which limits their size. In addition, they present poor plasticity, compared with crystalline materials, which restricts their application at room temperature. To overcome these problems, powder metallurgy could be a solution. To consolidate amorphous powders, innovative methods have been developed, such as laser or electron beams melting or spark plasma sintering (SPS). Laser melting can produce complex geometries samples, but often induces partial crystallization of the amorphous phase. With SPS, only simple geometry samples can be obtained, but the amorphous phase is preserved. The present paper addresses the influence of the processing conditions on the densification and mechanical properties of the AMZ4 (Zr_(59.3)Cu_(28.8)Al_(10.4)Nb_(1.5)) commercial powder obtained by SPS. Dense amorphous metallic glass material with 1500 MPa compression yield strength are obtained. Poor plasticity is observed compared to cast materials but this problem has been solved by addition of Ta crystalline particles in the Zr-Cu-Al-Nb amorphous matrix.