Abstract
The formability and sintering behavior of Ni60Nb15Ti20Zr5 metallic glass powder prepared by gas atomizing was investigated using precise hot press equipment. The structure of atomized metallic glass powder depended on its particle size, and only glassy phase was observed when the particle size was under 53μm. The glass transition temperature (Tg), crystallization temperature (Tx), and supercooled liquid region (ΔTx=Tx-Tg) of the Ni-based metallic glass powder was 838 K, 888 K and 50 K, respectively.
The hot press sintering under the precise control of temperature and pressure was conducted. The densification behavior depended on only working temperature, and the Ni-based metallic glass powders were consolidated to nearly full density by hot press sintering with working temperature range 863-883 K. On the other hand, the crystallization behavior depended on working time as well as working temperature. In the experimental study this time, the hot press condition achieving both full densification and no crystallization was temperature of 868 K and pressure of 200 MPa. The sintered body of full densification and no crystallization exhibited high corrosion resistance nearly equal to Alloy C-276.
