A series of Cu-Hf-Ti alloys prepared by rapid solidification of the melt and by copper mould casting were studied in the present work. Alloy ingots were prepared by arc-melting mixtures of pure metals in an argon atmosphere. An indication of the cooling rate obtained was determined using an Al-4.5 wt%Cu alloy. Cooling rates varied from 540 K/s for the centre section of a 4 mm die to 885 K/s for the outside wall section of the 2 mm die. The glass-forming ability, structure and thermal stability of Cu-Hf-Ti glassy alloys were studied by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and differential thermal analysis (DTA). Bulk glass formation was observed for the Cu64Hf36, Cu55Hf25Ti20 and Cu56Hf25Ti19 alloys, with critical diameters dc for a fully glassy structure of 1, 4 and 5 mm, respectively. The substitution of Hf by Ti increased the glassforming ability (GFA) and the thermal stability.
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机译：在本工作中，研究了通过熔体的快速凝固和铜模铸造制备的一系列Cu-Hf-Ti合金。合金锭是通过在氩气气氛中将纯金属的混合物电弧熔化而制得的。使用Al-4.5 wt％Cu合金确定获得的冷却速率。冷却速率从4 mm模具中心部分的540 K / s到2 mm模具外壁部分的885 K / s不等。通过X射线衍射（XRD），差示扫描量热法（DSC）和差示热分析（DTA）研究了Cu-Hf-Ti玻璃态合金的玻璃形成能力，结构和热稳定性。对于Cu64Hf36，Cu55Hf25Ti20和Cu56Hf25Ti19合金，观察到大块玻璃的形成，其完全玻璃化结构的临界直径dc分别为1、4和5 mm。用Ti代替Hf可提高玻璃形成能力（GFA）和热稳定性。
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