MECHANICAL BEHAVIOR OF INTERMETALLIC COMPOUNDS.
Rept. for 15 Sep 63-15 Sep 64,
MANLABS INC CAMBRIDGE MASS
Pagination or Media Count:
The aging behavior of the intermetallic compounds VCo3, VNi3, and VNi2 was investigated as a function of temperature, time, and composition. The disordered hightemperature structure of all compounds is f.c.c., and the ordered structures existing at lower temperatures are hexagonal, tetragonal and orthorhombic, respectively. Room temperature microhardness measurements were obtained from stoichiometric specimens of the three compounds initially quenched from the disordered state to aging temperatures of 400, 600, and 800C, and from several off-stoichiometric composition specimens of VCo3 and VNi3 aged at 600C. In addition, electrical resistivity and hot hardness measurements were obtained as a function of temperature for the stoichiometric compositions. The structures developed in these specimens by aging were defined by light microscopy and X-ray diffraction analysis and, for VNi3 by transmission electron microscopy. The observed hardness values obtained as a function of aging time are discussed in terms of crystallographic structure, transformation mechanism, microstructure, and the degree of long range order. Author