The microstructures of (β + γ) silver-tin alloys are especially influenced by both homogenization temperature and subsequent heat treatment. When the alloy is cooled from homogenization temperatures above approximately 200°C, lenticular regions of the ordered orthorhombic γ phase precipitate from within the disordered h.c.p. β_phase on three structurally equivalent planes, (1210), (1120), and (2110), to form a Widmanstatten structure. When the duplex alloys were homogenized at temperatures below approximately 200°C, where the β/(β + γ) phase boundary is vertical, these structures were not observed.
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