|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Solid State Precipitation
||Effect of Metalloid Addition on Anomalous Primary Crystallization of Al-RE Metallic Glasses
||Mustafacan Kutsal, Burcu Cam,
|On-Site Speaker (Planned)
Marginal glass forming alloys are known to show an anomalous primary crystallization reaction with unusually high nanocrystal number densities upon thermal devitrification. In order to get an insight of this puzzling behavior, we have studied the as-quenched states and devitrification of marginal glass forming Al90Y10 and Al87Y10Si3 metallic glasses with differential scanning calorimetry, X-ray diffraction, transmission electron microscopy and microhardness measurements. Our studies have shown that medium-range structural heterogeneity caused by chemistry alteration have direct impact on primary crystallization of Al-RE metallic glasses. Thermal analysis revealed that primary crystallization temperature is reduced from 480 K to 380 K with the addition of Si. Furthermore, microhardness measurements have showed 400 Hv hardness for Al87Y10Si3 metallic glasses, an ultrahigh value as compared to other Al-Rare-Earth based aluminum alloys. The underlying effects of Si addition will be discussed in detail with respect to short-to-medium-range correlations and corresponding structural models.
||Planned: Supplemental Proceedings volume