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采用铜模吸铸法制备出La62.0Al15.7(Cu0.5Ni0.5)22.3大块金属玻璃,经高压处理后,用X射线衍射仪(XRD)和示差扫描量热计(DSC)对非晶的结构驰豫和晶化过程进行了研究。结果表明,非晶玻璃转变温度和第一晶化温度随着压力的增加,其先增加后减小,极大值出现在4.0GPa的压力。这种现象归因于经过高压处理后玻璃转变温度区焓的变化,而焓的变化由基体缺陷激活体积引起自由体积变化所导致。此外,高压处理还影响玻璃的结晶过程。
La62.0Al15.7 (Cu0.5Ni0.5) 22.3 bulk metallic glass was prepared by copper mold suction casting method. After high pressure treatment, the glass was characterized by X-ray diffraction (XRD) and differential scanning calorimeter (DSC) Crystal structure relaxation and crystallization process were studied. The results show that the glass transition temperature and the first crystallization temperature increase first and then decrease with the increase of pressure, and the maximum appears at 4.0 GPa. This phenomenon is attributed to the change of enthalpy in the glass transition temperature zone after high-pressure treatment, while the change of enthalpy is caused by the free volume change caused by the matrix defect activation volume. In addition, high pressure treatment also affects the glass crystallization process.