Serration, deformation band propagation and strain marking in a 5083 aluminum alloy at low temperature

Abstract

Relations among load fluctuation, geometrical shape and propagation behavior of a deformation band were examined for an inhomogeneous plastic deformation generated at relatively low temperature. The geometrical shape and propagation behavior of the deformation band were evaluated by strain gauges and surface roughness of specimen. Quantitative analysis of the load fluctuation was also carried out by fast Fourier transform method. The following results were obtained. A wavy load fluctuation was observed in two-deformation regions; i.e., one of which was a yield deformation region and the other was a serration one. The geometrical shape and the tilt of the deformation band in each deformation region were similar, while the number of cycles, the velocity of propagation and the amount of increasing strain were different each other. However, it was clearly shown that the wavy load fluctuation generated in each deformation region resulted from a continuous propagation of the deformation band.