Abstract
Copper Σ3{111} and Σ9{221} symmetrical ‹110› tilt bicrystals and their component single crystals were tensile tested at room temperature. By the stress-strain curves obtained and the observation of slip lines, the effect of grain boundary on plastic deformation was discussed. The effect of grain boundary on the deformation behavior depended on the crystallographic relationship between the grain boundary planes and the primary slip planes in the two component single crystals. When both of the primary slip planes in the component single crystals were parallel to the grain boundary, the difference of the stress-strain curves between the bicrystal and the component single crystal was not found. On the other hand, when the primary slip planes in the bicrystal were not parallel to the grain boundary, the grain boundary raised the flow stress of the bicrystal above that of the component single crystal. In case of the bicrystals in which the multiple slips take place in the component single crystals, no effect of the grain boundary on the deformation behavior of the bicrystal was observed.
