Abstract
o estimate CRSSs of slip systems in hcp crystals, shear tests of magnesium single crystals were carried out at room temperature. In the shear test, basal slip occurred within shear deformation area, and CRSS of the basal slip was estimated as 0.35MPa. However, specimens for prismatic slip deformed with {101^^-2} twin. The test result shows that CRSS of prismatic slip in magnesium will be more than 90MPa. To estimate CRSS of the prismatic slip precisely, alternate specimens for shear test should be necessary.