Abstract The strength and toughness of alumina can be enhanced by adding silver inclusions. In the present study, the corrosion behaviour of such Al 2O 3 Ag composites in nitric acid is investigated. The strength of the composites containing 2.5 vol% silver is not affected after the corrosion test. However, the weight loss of the composites containing 10 vol% silver is increased with increasing corrosion time. The strength and the toughness of the composites after corrosion are significantly degraded. For example, the strength of the composites containing 10 vol% silver is decreased by 50% and the toughness by 30%, when the composites are soaked in nitric acid for 1000 h.