The dynamic tensile fracture of vacuum-evaporated gold films was observed directly in a scanning electron microscope by sticking the film on the rubber substrate with Aron-alpha and then painting the edges with Dotite. Gold films from 2200 to 4000Å in thickness in this study were heated at different temperatures ranging from 100 to 700°C. The dynamic fracture strain was found to increase as the grain of films was increased approximately 0.5μm in diameter. The electron microscope observations of the fractured films showed that the fracture propagation occurred along grain boundaries by plastic deformation within the grains. The fracture strain ratio (εd/εs) of dynamic and static fracture gold films thicker than about 3000Å was usually of the order of 1.1 to 1.4.
