Study on Preparation of Ti-based Amorphous and Quasi Nano-crystalline Material
Be element in Ti50Ni15Cu25Sn3Be7 was replaced with Al and B to prepare Ti50Ni15Cu25Sn3Al6.9B0.1 amorphous alloy by melt-spining,copper suction casting,and then to prepare quasi nano-crystal with the amorphous alloy by heat treatment. SEM was used to observe microstructure and grain size. The XRD analysis shows that the sample prepared by copper suction casting includes crystal and little amorphous. The DTA analysis shows that there are three phase transition points,the transition temperature is that Te1=350 ℃,Te2=430 ℃,Te3=510 ℃. The average grain size of the alloy reduces to below 1 μm after oil quenching at 800℃×10 min and tempering at 350 ℃×12 h,while the grain growth is observed after tempering at 350 ℃×24 h,the average grain size is about 10 μm.