Mettler-Toledo GmbH, Analytical, 8606, Nänikon, Switzerland.
Laboratory of Metal Physics and Technology, Department of Materials, ETH Zurich, 8093, Zurich, Switzerland.
Nat Commun. 2019 Mar 22;10(1):1337. doi: 10.1038/s41467-018-07930-3.
Via fast differential scanning calorimetry using an Au-based glass as an example, we show that metallic glasses should be classified into two types of amorphous/monolithic glass. The first type, termed self-doped glass (SDG), forms quenched-in nuclei or nucleation precursors upon cooling, whereas in the so-called chemically homogeneous glass (CHG) no quenched-in structures are found. For the Au-based glass investigated, the critical cooling and heating rates for the SDG are 500 K s and 20,000 K s, respectively; for the CHG they are 4000 K s and 6000 K s. The similarity in the critical rates for CHG, so far not reported in literature, and CHG's tendency towards stochastic nucleation underline the novelty of this glass state. Identifying different types of metallic glass, as is possible by advanced chip calorimetry, and comparing them with molecular and polymeric systems may help to elaborate a more generalized glass theory and improve metallic glass processing.
通过使用基于金的玻璃作为示例的快速差示扫描量热法，我们表明金属玻璃应分为两种类型的非晶/整体玻璃。第一种类型称为自掺杂玻璃（SDG），在冷却时形成淬火核或成核前体，而在所谓的化学均匀玻璃（CHG）中则没有发现淬火结构。对于所研究的基于金的玻璃，SDG 的临界冷却和加热速率分别为 500 K s 和 20,000 K s；对于 CHG，它们分别为 4000 K s 和 6000 K s。CHG 的临界速率相似，到目前为止在文献中尚未报道，并且 CHG 具有随机成核的趋势，突出了这种玻璃状态的新颖性。通过先进的芯片量热法识别不同类型的金属玻璃，并将其与分子和聚合物系统进行比较，可能有助于阐述更广义的玻璃理论并改进金属玻璃的加工。
