Fatigue behavior after pre‐corroded in a simulated body fluid for ZK60 magnesium alloy prepared by micro‐arc oxidation

Abstract A bio‐ceramic coating was prepared on the surface of ZK60 magnesium alloys by micro‐arc oxidation (MAO) method. The substrate (BM) and coated (MAO) specimens were pre‐corroded in a simulated body fluid (SBF) for 12 h. Strain‐controlled and stress‐controlled loading modes were used to conduct fatigue tests for the specimens with non‐corroded and pre‐corroded, and the cyclic deformation behavior of different specimens was studied. The fatigue life of pre‐corroded MAO specimen is higher than that of pre‐corroded BM specimen. The mechanism of cyclic deformation under different loading conditions is related to twinning and slip. For the same specimens, the higher the absolute value of ratcheting strain, the lower the fatigue life. A modified total strain energy model is proposed, and the precision of life prediction is higher than that of traditional fatigue model.