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Transformation twinning

Figure 3.26 Transformation twinning a cubic crystal (a) will become tetragonal on cooling if the length of one axis changes (b, c) (d) the resulting deformation is minimized by twinning. Figure 3.26 Transformation twinning a cubic crystal (a) will become tetragonal on cooling if the length of one axis changes (b, c) (d) the resulting deformation is minimized by twinning.
Transformation twins arise on cooling a crystal because of ... [Pg.131]

In general, a low-temperature polymorph has lower symmetry than a high-temperature polymorph. So, in the phase transformation from high- to low-temperature polymorph, the low-temperature polymorph can have two orientations, which leads to twin formation. This is called the transformation twin. To minimize the interface energy between twinned individuals through transfer-... [Pg.136]

Transformation Twinning of Z 2(CsCl)-Type Structure Based on an Inhomogeneous Shear Model Frederick E. Wang... [Pg.147]

Whenever a crystal transforms (usually on cooling) to a lower symmetry structure in which a number of orientational variants are possible, transformation twins are an almost invariable consequence if the new phase is nucleated at several different places in the original structure. The formation of Dauphine twins at the jS-to-a transformation in quartz is a classic example, which has already been mentioned briefly in Section 8.6. We now consider the twins and modulated structures associated with the monoclinic-to-triclinic transformation in the K feldspars, KAlSisOg. [Pg.226]

A particularly interesting type of transformation twinning has been observed by Reeder and Nakajima (1982) in dolomite the twin boundaries resemble antiphase domain boundaries (see Section 8.8). Modulated structures are also observed in dolomites (van Tendeloo, Wenk, and Gronsky 1985 Wenk, Barber, and Reeder 1983). [Pg.234]

Harrison R.J., Redfem S.A.T. The influence of transformation twins on the seismic-frequency elastic and anelastic properties of perovskite dynamical mechanical analysis of single ciystal LaAlOj. Physics of the Earth and Planetary Interiors 2002 134 253-72. [Pg.146]

FIG. 23 Transmission electron micrographs of PBl single crystals (a) lath-shaped orthorhombic crystals (b) terraced orthorhombic crystals (c) terraced tetragonal crystals (d) hexagonal crystals (e) transformation twin from the orthorhombic to the hexagonal modification. (Reprinted from Ref 202.)... [Pg.198]

Figure 4. Transmission electron micrograph showing internal transformation twins in an Fe-Ni-C alloy martensite... Figure 4. Transmission electron micrograph showing internal transformation twins in an Fe-Ni-C alloy martensite...
See other pages where Transformation twinning is mentioned: [Pg.121]    [Pg.114]    [Pg.378]    [Pg.378]    [Pg.571]    [Pg.128]    [Pg.136]    [Pg.137]    [Pg.147]    [Pg.19]    [Pg.37]    [Pg.226]    [Pg.17]    [Pg.60]    [Pg.65]    [Pg.367]    [Pg.381]    [Pg.286]    [Pg.265]    [Pg.265]    [Pg.266]    [Pg.197]    [Pg.164]   


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Transformation-induced twinning and modulated structures

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