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Although it is not often encountered, the stress corrosion cracking of low caratage gold alloys occurs in certain environments. This article reviews this phenomenon, wha.t is known of its mechanism, and thé ways in which it may be avoided or prevented.Stress corrosion cracking is the local rupture of a metal or an alloy under the combined effects of corrosion and stress at levels well below those at which they would cause failure, were they acting independently. The phenomenon is accompanied by little evidence of corrosion products or elongation of the alloy and, as such, may leem to be spontaneous (1). Liquid metal embrittlement of pure metals has also been reported, but is generally considered to be a special case, as stress corrosion is observed in alloys rather than pure metals (2).Stress corrosion has been the, subject of much research, more usually with the intention of assessing the suitability of an alloy for a particular purpose, rather than to understand the detailed mechanism by which the phenomenon occurs. A very common incentive for such research when applied to gold-containing alloys has been the development of alternatives to the range of existing alloys which would be cheaper and yet have relatively low susceptibility to stress corrosion cracking. The main outcome of this research has, however, been an increase in the number of alloy/environment combinations known to be subject to stress corrosion cracking, rather than the development of a wide range of resistant alloys.

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