Effect of cold rolling on glass transition of Zr55Al10Ni5Cu30 bulk metallic glass
(1. State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering,
Shanghai Jiao Tong University, Shanghai 200240, China;
2. School of Materials Science and Engineering, Taiyuan University of Science and Technology,
Taiyuan 030024, China)
Shanghai Jiao Tong University, Shanghai 200240, China;
2. School of Materials Science and Engineering, Taiyuan University of Science and Technology,
Taiyuan 030024, China)
Abstract: Zr55Al10Ni5Cu30 bulk metallic glass was prepared through water-cooled copper mold suction casting, and was rolled up to 95% in thickness reduction. The structures and thermal stabilities of the as-cast and as-rolled specimens were examined by X-ray diffractometer and differential scanning calorimeter. As the thickness reduction increases, the crystallization onset temperature, peak temperature and the apparent activation energy of crystallization almost keep constant, while the glass transition temperature decreases from 681 to 671 K and the apparent activation energy of glass transition increases from (404±26) to (471±29) kJ/mol. The glass transition process is markedly affected by the rolling induced changes of microstructure and structural relaxation.
Key words: bulk metallic glass; cold rolling; glass transition