Effect of Zr on glass-forming ability and crystallization kinetics of Y56Al24Co20 metallic glass

✍ Scribed by Shiwen He; Yong Liu; Baiyun Huang; Zhantao Li; Hong Wu

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 493 KB
• Volume: 204
• Category: Article
• ISSN: 0924-0136
• DOI: 10.1016/j.jmatprotec.2007.11.030

✦ Synopsis

The effect of the Zr addition on the glass-forming ability (GFA) and crystallization kinetics of Y 56 Al 24 Co 20 alloy has been investigated. It is found that Y 46 Zr 10 Al 24 Co 20 has a reduced glass transition temperature as large as 0.626 at a heating rate of 20 K/min. Crystallization kinetic studies show that the activation energies derived from Kissinger equation for Y 46 Zr 10 Al 24 Co 20 metallic glass of E g = 415.64 kJ/mol, E x = 279.74 kJ/mol and E p = 319.51 kJ/mol for glass transition, onset crystallization and crystallization peak, respectively, which are higher than those values for Y 56 Al 24 Co 20 one. The dependence of the glass transition on the heating rate was analyzed in terms of the Vogel-Fulcher-Tamman (VFT) equation. The glassforming ability of the alloy was discussed based on the composition-dependent melting behavior, the reduced glass transition temperature, and the fragility parameter. It is shown that substitution of 10 at.% Zr for Y improves the glass-forming ability and the thermal stability of Y 56 Al 24 Co 20 alloy.