||It has been reported that the Zr-based amorphous alloys exhibit high corrosion resistance, good mechanical properties, better thermal stability and good glass-forming ability. The thermal properties of the Zr-Al-Cu-Ni amorphous alloys could be improved by adding boron and silicon that also has been reported. Therefore, the Zr-Al-Cu-Ni amorphous alloys are chosen as the base materials for investigating the effect of the thermal properties by adding boron and silicon at the same time.|
According to the results of the experiment, the Zr60Al7.5Cu17.5Ni10B1Si4 amorphous alloy ribbons with the highest GFA index (g value) and the value is 0.42; the maximum supercooled liquid region (DTx) is about 85 K for the Zr60Al7.5Cu17.5Ni10B1Si4 amorphous alloy ribbons. For the isothermal analysis or non-isothermal analysis, the Avrami index (n value) is not constant, and the Zr60Al7.5Cu17.5Ni10B1Si4 amorphous alloy ribbons with the largest activation energy which was more than 300 kJ/mol. When the Zr60Al7.5Cu17.5Ni10B1Si4 amorphous alloy ribbons were heated to 721 K and held for 4000 seconds, the crystallized phases were ZrO2 with orthorhombic structure and Zr2Ni with tetragonal structure. When the Zr62Al7.5Cu17.5Ni10B2Si1 amorphous alloy ribbons were heated to 724 K and held for 4000 seconds, besides the ZrO2 phase with orthorhombic structure and the Zr2Ni phase with tetragonal structure, a Zr2Ni crystallized phase with cubic structure is also included. According to the observation of the TEM image for heating Zr62Al7.5Cu17.5Ni10B2Si1 amorphous alloy ribbons to 694 K and held for 4000 seconds, there are many grains distribute in the amorphous matrix, and the grain size is about 20 ~40 nm.