Amorphous-crystalline Al-based laminates with enhanced plasticity produced by high pressure torsion

The consolidated disks consisted of two melt-spun Al86Ni9Gd5 amorphous ribbons inserted between two-layered stacks of Al foils were obtained by using unconstrained high-pressure torsion straining. Structure and mechanical properties of the Al-covered samples were studied by scanning electron microscopy, three-point bending testing and microhardness measurements and compared with those of consolidated disks consisted of two amorphous ribbons and of 12 layers of Al foils. It was established that the Al-covered disks had superior plasticity (3.6%) and intermediate average microhardness (1.95 GPa) compared with those of the uncovered and Al consolidated disks. The mixing of the Al and amorphous alloy was directly observed in the Al-covered disks which resulted in ductilisation and large variations of microhardness on surface and inside of the samples.