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Abstract: Objective: To compare the corrosion behaviours of two aluminium bronze, dental casting alloys during a standard immersion test and for immersion in neutral saline. Methods: Cast specimens of aluminium bronzes with 1.4wt% Fe (G) and 4wt% Fe (N) were subject to progressively longer periods (up to in total 7 days) immersed in 0.1M saline, 0.1M lactic acid solutions and examined by scanning electron microscopy with EDX analysis. Immersion in 0.1M neutral saline was for 7 days. Results: In the acidic solution, exposed interdendritic volumes in alloy N corroded completely away in 7 days with dissolution of Ni-enriched precipitate species as well as the copper-rich matrix. Alloy G begins to corrode more slowly but by a similar mechanism. The number density of an Fe-enriched species is insufficient to maintain a continuous galvanic potential to the copper matrix, and dissolution becomes imperceptible. In neutral saline solution, galvanic action alone caused pit-etching, without the dissolution of either precipitate species. Significance: The upper limit for the total dissolution of metallic ions in the standard immersion test can be set at 200μgcm−2. Aluminium bronze dental alloys can be expected to release both copper and nickel ions into an acidic oral environment. [Copyright &y& Elsevier]