Corrosion fatigue of three steels namely: AISI 1018, AISI 4340 and 17-7 PH stainless steel are investigated in various environments. Testing mediums chosen are natural seawater, polluted sea water from an industrial site, drinking tap water produced by desalination process, 4% sodium chloride tap water solution and a laboratory air environment. Results obtained for the three steels are consistent in pointing out that pollutants in seawater do not contribute to an acceleration of corrosion fatigue. The aggressiveness of drinking water is attributed to its chemical instability, low alkalinity and bicarbonate content.

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Creep rupture tests have been conducted on specimens of AISI 1018 low carbon steel pre-exposed to various environments: polluted seawater, natural seawater, industrial seashore tide, drinking tap water, and industrial air. Exposure to increasingly corrosive environments before creep testing results in decreasing creep strength by appreciable amounts. With suitable extrapolation procedures, creep rupture test data may be cautiously used to generate design creep curves involving service temperature, stress, and life for precorroded steel. Further experiments are needed to investigate the combined effect of corrosion and creep on rupture life over a wider range of environmental test parameters.