大块非晶合金的玻璃形成能力

Glass Forming Ability of Bulk Amorphous Alloys

对描述大块非晶合金玻璃形成能力(GFA)的各种判据△T、K_(gl)、S、△T_x、T_(rg)、F_(BMG),以及用理论公式、TTT曲线法、CCT曲线法计算的形成大块非晶所需的临界冷速R_c进行了分析和讨论。结果表明,这些大块非晶合金的GFA判据在一定程度上可以反映大块非晶合金的某些性质,但单一的判据不能直观地表征大块非晶合金的GFA大小,根据TTT曲线及CCT曲线得到的临界冷速R_c及所能制备的大块非晶合金的最大尺寸t_(max)是表征大块非晶玻璃形成能力的基本参量。

Various criteria which characterize the glass forming ability (GFA) of bulk amorphous alloys, such as △T~*, K_(g1). S, △T_x, T_(Ig) and F_(BMG), and critical cooling rate R_c calculated by formula, TTT curves or CCT curves, are analyzed and discussed. The results indicate that these GFA criter a can reflect some properties of bulk amorphous alloys to some extent, but any single criterion can not characterize the GFA directly. The most reliable criteria are critical cooling rate R_c derived from TTT curves or CCT curves and the largest sample size t_(max) of bulk amorphous alloys that can be fabricated.