Low-energy (110) twist boundaries were studied. Four low-energy orientations were observed by using the particle rotation method, with (110)Ag crystallites sintered onto the (110) surface of a monocrystalline Ni substrate. They were characterized by twist angles of 0, 35, 55 or 70°, measured between the 2 close-packed directions of the crystals at the boundary. The determination of the orientation of the samples was carried out by means of transmission electron microscopy. Reorientation of the particles occurred in 2 ways: by continuous rotation or by twinning. In samples with initial twist angles of 3, 35 or 49°, a progressive rotation of the particles was observed. The Ag particles in samples with a 70° initial twist reoriented to 0° via the nucleation and growth of twins which had parallel crystallographic directions with the Ni substrate. Samples with initial twist angles of 58 or 65° exhibited both types of reorientation. While the particles underwent continuous rotation, twins nucleated and grew within the particles.

S.M.Allameh, S.A.Dregia, P.G.Shewmon: Acta Metallurgica et Materialia, 1994, 42[10], 3569-76