反复熔炼对Zr基大块非晶合金玻璃形成能力的影响

Effect of repetitive melting on glass forming ability of Zr-based alloys

研究了反复熔炼对Zr60 Al15Ni2 5和Zr65Al7.5Ni10 Cu17.5合金的玻璃形成能力的影响。DSC分析表明 ,随着熔炼次数的增多 ,Zr60 Al15Ni2 5非晶合金的玻璃转变温度和晶化开始温度都提高 ,而Zr65Al7.5Ni10 Cu17.5非晶合金的特征温度基本没有发生变化。Zr60 Al15Ni2 5合金的熔化焓由于反复熔炼而降低 ,在热力学上有利于非晶相的形成。根据反复熔炼对铸锭凝固组织进而对合金熔体中的短程序的影响 ,讨论了玻璃形成能力的变化及原子间的结合力对短程序尺寸的影响 ,分析了 2种合金对反复熔炼处理的敏感性的不同。

The effects of repetitive melting on the glass forming ability (GFA) of Zr 60Al 15Ni 25 and Zr 65Al 7.5Ni 10Cu 17.5 were investigated. The results of DSC curves indicate that the glass transition temperature and the crystallization onset temperature of Zr 60Al 15Ni 25 alloy increase as melting times increase. However, the characteristic temperatures of Zr 65Al 7.5Ni 10Cu 17.5 alloy scarcely change after repetitive melting. The reducing of fusion enthalpy of Zr 60Al 15Ni 25 alloy after repetitive melting contributes to the suppressing of the nucleation of the primary phase. The improvement of the GFA of Zr 60Al 15Ni 25 alloy is attributed to the smaller size of short-range orders, inheriting from the solidification structure of the ingot, after repetitive melting. Based on the fact that the attraction interaction of different species atoms controls the size of short-range orders in the liquid, the different sensitivity of the two alloys to repetitive melting was discussed.