Deformation induced martensitic transformation and strong workhardening behaviours in nanostructured Zr-Cu-Al alloys

The bulk as cast Zr50Cu50-xAlx alloys with various microstructural phase constituents were prepared by copper mould casting. It is found that the mechanical properties and workhardening behaviours of Zr50Cu50-xAlx alloys strongly depend on the microstructural phase constituents. The Zr50Cu44Al6 glassy composites constituted by ZrCu(B2) austenite and ZrCu martensite are able to achieve high strength and large plastic deformation together with pronounced workhardening. The ZrCu martensitic alloys show plastic deformation and workhardening. The Zr50Cu47Al3 diphase alloy constituted by ZrCu (B2) austenite and ZrCu martensite provides ultrahigh workhardening ability (H-c = 3.21) as expected for a deformation induced martensitic transformation. For the alloy containing ZrCu (B2) austenite phase, the deformation induced martensitic transformation is believed to cause a strong workhardening and contribute to a large compression deformability.