Effects of Pre-Deformation and Annealing on Mechanical Properties of Ti-Based Amorphous Alloys

Abstract:

Ti₄₀Ni₄₀Cu₂₀ amorphous matrix composite plate specimens were fabricated in the levitation suspend melting - water cooled Cu mold process. The specimens were by pre-compressed at different degrees with a pressure testing machine and then annealed at 150 ℃ for approx. 30 min. And the effects of the predeformation and annealing processes of the microstructure and mechanical properties of the Ti₄₀Ni₄₀Cu₂₀ alloy system were studied. The results show that the austenite phase into the martensitic phase transformation under external force occurred then. The phase transition induced by the deformation coupled with the annealing release of residual thermal stress plays a role in enhancing both strength and toughness of the amorphous matrix composite. Both martensite phases and austenite phases are increased with the increase in the degrees of pre-deformation, but martensite phases are increased faster. Thus the yield strength of the composite increased, while the ductility reduced .Therefore the controllable yield strength in the pre-compression stage for shaping can be realized.