Phase transition in the Zr60Al15Ni25 bulk metallic glass subjected to rolling at room temperature

• 作 者: YAN Zhijie LI Jinfu ZHOU Yaohe
• 机 构: State Key Laboratory of Metal Matrix Composites,School of Materials Science and Engineering,School o
• 出 处: 中国科学E辑（英文版）
• 发表日期: 2004年期
• 关键词: metallic glasses plastic deformation phase transformations shear bands
• 基金项目: 国家自然科学基金;高等学校博士学科点专项科研项目;太原科技大学校科研和教改项目;the Shanxi Provincial Foundation for Leaders of Disciplines in Science;山西省自然科学基金

The microstructure evolution of the Zr60Al15Ni25 metallic glass during rolling at room temperature is investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and high-resolution transmission electron microscopy (HREM). The results show that the values of full width at half maximum (FWHM) of the XRD patterns and exothermic enthalpy △H of DSC plots do not monotonically change with the variation of deformation degrees ε. As ε is not larger than 20%, the values of FWHM and △H are lower than that of the as-cast state. When ε reaches 30%, the values of FWHM and △H become larger than that of the as-cast state, while their values begin to decrease again as ε reaches about 85%. These results indicate that the reversible transitions between ordered and disordered atomic configurations occur during rolling, which is further verified by the HREM images. The reversible phase transition can be explained by the competition between the diffusion controlled reordering and shear-induced disordering during rolling.