Article ID: M2019049
The log angles of a rotation matrix are three independent elements of the logarithm of the rotation matrix. Nye’s lattice curvature tensor κij is discussed by using the log angles. For the change in a crystal orientation ΔR with the change in a position Δxi, it is shown that the elements of κij are written as κij = Δωi/Δxj using the log angles Δωi of ΔR. The log angles for the crystal rotation given by the axis/angle pair are also discussed.
This Paper was Originally Published in Japanese in J. Japan Inst. Met. Mater. 82 (2018) 415–418.