Plastic deformation of aluminum bicrystals 〈100〉 oriented

Abstract The effect of grain boundaries on the plastic properties of symmetrical 〈100〉 aluminum bicrystals having various angles of tilt boundaries was studied. It was found that these bicrystals deform by the mode similar to that of the 〈100〉 oriented aluminum single crystal. Fine multiple slip which appeared in the early stage of the deformation is suppressed at the boundary. Afterward, clustered slip accompanying the prominent cross slip can pass the 4° and 14° boundaries which have a small difference in orientation. For the 37° boundary, which has a large misorientation, clustered slip cannot pass the boundary and multiple slip is introduced at the boundary. It was found that the flow stresses of these bicrystals are almost equal to those of the component single crystals. Therefore, it is considered that the formation energy of grain boundary dislocations formed after the passage of dislocations from one grain to another does not contribute to an increase in flow stress after multiple slip has occurred.