ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Natural chalcopyrite (CuFeS2) specimens from Golden, New Mexico and Transvaal, South Africa were examined by transmission electron microscopy. The defect structure was composed of dislocations, dislocation loops, tangles, and substructure (including dislocation networks), stacking faults on {112} (both intrinsic and extrinsic), and mechanical twins and twin-faults. Optical microscopy indicated a large grain structure (0.3 to 0.5 cm grain size) containing numerous large twins similar in size to the average grain diameter. It is concluded that the absence of superdislocations of the type 1/4 〈201〉 is a result of the CuFeS2 structure approximating more closely the sphalerite lattice as a result of the c/a ratio approaching 2. It is also concluded that the apparently low stacking fault free energy in CuFeS2 will give rise to abundant mechanical twins accommodating large deformations, and this may be an important factor in the grinding and leaching of chalcopyrite concentrates. The observations suggest that the defect structure, particularly the occurrence of superdislocations and antiphase boundaries, might increase with a decrease in the c/a ratio for chalcopyrite structures, and this may have an important influence on the electrical and mechanical properties of compounds having the chalcopyrite structure.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00540848
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