Controlling the pressure distribution in thermoplastic molding of metallic glass through in-situ merging kinetics

Metallic glasses can be patterned on a nanometer scale by thermoplastic molding to generate durable replicas of master templates. However, the pattern area and uniformity are inherently limited by the alloy-dependent sample size and the nonuniform pressure distribution in molding. Here, we demonstrate a novel technique to overcome both limitations simultaneously by manipulating the supercooled liquid merging kinetics. The results from Pt-based metallic glass reveal that molding small samples with controlled arrangement and spacing can generate patterns over large areas with improved uniformity. The spatial distribution of pressure is modified by controlling the merging kinetics of individual samples. Distributed pressure fields enable uniform template filling over large area in multi-sample molding compared to conventional single-sample approach. The experimental results for single- and multi-sample molding are compared with analytical predictions based on the lubrication theory. The findings suggest that the use of multiple small samples is a better approach for thermoplastic molding and drawing of metallic glasses.