Preparation and properties of Ni68.6W17.9B13.5 metallic glass
(State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China)
Abstract: A novel Ni-based metallic glass, i.e., Ni68.6W17.9B13.5 (mole fraction, %), was prepared using melt spinning method. The results showed that the element B has much effect on the glass forming ability of the Ni-W-B metallic glass. Ni-W-B metallic glass could not be fabricated with lower content of B, whereas a higher content of 13.5% B could easily lead to the fully amorphous structure. The glass transition temperature and the onset temperature of crystallization are as high as 768 K and 781.5 K, respectively, and the crystallization activation energy calculated by Ozawa model is (637±60) kJ/mol, which showed strong thermal stability of Ni68.6W17.9B13.5 metallic glass. This novel Ni-based metallic glass also exhibited good mechanical properties with the tensile strength of about 2331 MPa. The results indicate that this metallic glass should have a promising application in high strength material.
Key words: Ni-based metallic glass; activation energy; thermal stability; tensile strength