Interpretation of tweed contrast from the YBa₂Cu₃O_7-δ system

Twin walls and hierarchical mesoscopic structures

“…Depinning energies are often large compared with thermal energies for diffusion. This leads to very long kinetic time scales for twin coarsening, long enough for the technological device applications of needle shaped domain structures (Zhu et al, 1993;van Tendeloo et al, 1990;Schmahl et al, 1989).…”

“…64(2), pp. 201-211 # 2000 The Mineralogical Society * E-mail: es10002@esc.cam.ac.uk 1989; Lacayo et al, 1992;Putnis and Salje, 1994;van Tendeloo et al, 1990;Zhu and Cowley, 1994;Zhu et al, 1990Zhu et al, , 1993. The disadvantage of this method is not only that its images are restricted to small areas of the specimen but also that it appears to be dif cult to extract quantitative information about the structural features of ferroelastic domain walls such as the thickness of twin walls.…”

Investigation of Multiply Twins in Mn2.02Co0.98O4 Ceramic by Means of Transmission Electron Microscopy

“…Indeed, twins have long been identified in many materials, including metals, spinel semiconductors, superconductors, titanates, etc., and have attracted materials researchers’ great interest. Among the above‐mentioned materials, we note that twins in metals, superconductors and titanates are systematically studied . It is conclusion that the formation of twins and the interaction between twins and dislocations are the mainly reasons causing the strain hardening in metal materials .…”

“…Among the above-mentioned materials, we note that twins in metals, superconductors and titanates are systematically studied. [45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60][61] It is conclusion that the formation of twins and the interaction between twins and dislocations are the mainly reasons causing the strain hardening in metal materials. 49,52,62,63 In addition, twins can increase the roomtemperature resistivity of metal.…”