MICROSTRUCTURAL CHARACTERIZATION OF HEXAGONAL (AG, CU)ZN(4) ALLOYS IN THE DEFORMED AND AS-CAST STATE

Zn-based ternary alloys containing Ag and Cu as solutes having characteristic hexagonal close-packed (hcp) structure (Ag, Cu)Zn4 have been studied for microstructural evolution in the deformed and as-cast state in order to correlate the microstructure with mechanical property of the materials. X-ray diffraction (XRD) line profile analysis, optical microscopy and scanning electron microscopy (SEM) have been used to study the microstructure and the mechanical property studied through the measurement of microhardness. X-ray studies of the deformed alloys reveal increased influence of solute Cu in the generation of deformation stacking fault of density alpha with increasing solute concentration. A reasonably good estimate of stacking fault energy parameter (gamma/mu) for the alloys has also been made. Increased influence of solute Cu has also been observed to control the grain sizes and microhardness. A close correlation could be establised between the microstructural parameters and microhardness signifying the interdependence of mechanical property with microstructure of the alloys.