Flow and fracture of free-standing Ag and Cu thin films and Ag/Cu multilayers.

Free-standing polycrystalline films of Ag, Cu and Ag/Cu multilayers were tested in tension using an optical diffraction grating for the measurement of the strain. The yield stress and the rate of work hardening both increase strongly with decreasing layer thickness. These effects combine to raise the stress for ductile fracture up to 700 MPa and to lower the maximum plastic strain. [ABSTRACT FROM AUTHOR]