Journal article
Structure of the Dislocation in Sapphire
Experimental evidence of the existence of 01 0 dislocations in the {2 0} prism planes in sapphire has been obtained by transmission electron microscopy. By the weak-beam technique it has been shown that the 01 0 dislocations may dissociate into three partials. The partials all have a Burgers vector of ⅓ 01 0 and are separated by two identical faults.
The distance between two partials is in the range 75-135 Å, corresponding to a fault energy of 320±60 mJ/m2. Perfect 01 0 dislocations have also been observed. These dislocations exhibited either one or two peaks when imaged in the (03 0) reflection by the weak-beam technique. The interpretation of the electron micrographs has been supported by computer simulation of the dislocation images.
A faulted dipole has been observed, indicating that some of the prismatic loops often seen to lie in rows along [0001] are faulted with a ⅓ 01 0 Burgers vector. A mechanism for the dipole formation is suggested.
Language: | English |
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Year: | 1976 |
Pages: | 877-889 |
ISSN: | 00318086 |
Types: | Journal article |
DOI: | 10.1080/14786437608221921 |