Shear punching of bulk metallic glasses under low stress

Abstract

Bulk metallic glasses (BMGs) possess excellent mechanical properties yet poor efficient processing ability at room temperature which limits the application of BMGs. Here, we report a high efficiency and energy-saving punching method suitable for processing of BMGs. By use of ultrasonic vibration on the punch, the accurate shape can be quickly manufactured from a BMG plate with a thickness upon 1 mm at an extremely low punch pressure of 110 MPa, which is less than one tenth of the estimated value by conventional theory. The underline physical mechanism of softening in BMG during the ultrasonic vibration assisted punching process was interpreted by cyclic liquefaction or the activation and connection of liquid-like regions in the elastic matrix of BMGs. This work would provide a novel route for solving the machining problem of BMGs at room temperature and promote wider applications of BMGs in precision manufacturing field.