An X-Ray Study of Tin-Nickel Electrodeposits

An X-ray investigation of the crystal structure and textural properties of tin-nickel alloy electrodeposits is described.A metastable nickel arsenide type structure, similar to that of gamma dash Ni3Sn2, characterises the alloy electrodeposit. The hexagonal structure cell constants a0 = 4·15 Å, c0 = 5·10 Å, c/a = 1·23 differ appreciably from established values for Ni3Sn2, and the differences result from the change in composition from Ni3Sn2 towards NiSn that is induced by the conditions of electrodeposition. The alloy deposit is stable up to 300° C, but decomposes on heating above this temperature.A strongly marked preferred orientation texture is found in bright tin-nickel electrodeposits, and an analogy with bright speculum is evident.