The Measurement Of Excess Volume At Grain Boundaries Using Transmission Electron Microscopy

A technique enabling accurate measurements of relative displacements between adjacent coincidence related crystals has been described previously. The technique depends on intensity measurements of stacking‐fault‐like fringes by comparison of experimental and theoretically simulated fringe profiles. This matching procedure is illustrated in the present work for a (l̄2l̄) boundary between twin related aluminium crystals. The main part of the paper describes the application of the technique for measuring excess volume at certain coincidence boundaries, and considers in detail the measurement for (l̄2l̄) boundaries. The excess volume per unit area at (l̄2l̄) boundaries is found to be 0·02 nm.