The Effect of Heating Rate on the Formability of Bulk Metallic Glass in a Supercooled Liquid Region
The formability of a Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass has been investigated in the present study in relation to the heating rate. A series of extrusion tests after rapid heating has been performed in a laboratory scale together with sheet forming tests after slow heating for comparison purpose. The basic processing map based on dynamic materials model (DMM) and compression test data has been utilized to evaluate feasible forming conditions. The macroscopic formability, classified by fully formed, partially formed or a catastrophic fracture, is found to have a good correspondence with the iso-efficiency contour in the processing map. The region of high power dissipation efficiencies with η>0.8 is found to be broaden by avoiding crystallization events due to reduced exposure time in extrusion process with a faster heating rate.
N. Ohno and T. Uehara
K. S. Lee et al., "The Effect of Heating Rate on the Formability of Bulk Metallic Glass in a Supercooled Liquid Region", Key Engineering Materials, Vols. 340-341, pp. 59-64, 2007