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A B S T R A C T For high-cycle fatigue of metals, the DC electrical resistance is a more sensitive parameter to the initiation of micro-cracks during the irreversible fatigue damage accumulation process. This implies that the electrical resistance is a suitable parameter that can be consistent with the fatigue damage physical mechanism. The relation between the ratio of electrical resistance changes and the cyclic fraction of the fatigue specimen may reasonably represent deterioration in mechanical properties of structural steels during the high-cycle fatigue process. The high-cycle fatigue damage accumulation model based on electrical resistance for structural steels was proposed. The model was verified by some experimental data for three structural steels; normalized 45C steel, 20 Mn steel and 16 Mn steel, and good agreement was obtained. The corresponding fatigue lifetime on the basis of the electrical resistance model was also performed. The results show that the approach to fatigue lifetime prediction and failure based on the electrical resistance is a good non-destructive technique.A,Ã = apparent and effective cross-sectional areas of the damaged specimen A 0 = cross-sectional area of the initial specimen b = fatigue exponent of materials D, D c = damage variable of the damaged specimen, critical value of damage N , N f = elapsed cycles and cycles to failure of the fatigued specimen R, R = electrical resistances of the virgin specimen and the damaged specimen r = ratio of electrical resistance in the damaged state to electrical resistance in the virgin state r c , r (N f −1) = critical ratios of electrical resistance in the damaged specimen α = material parameter at a prescribed stress amplitude r = increment of ratio between electrical resistances in the damaged state and in the virgin state σ a = cyclic stress amplitude σ f = fatigue strength coefficient of materials I N T R O D U C T I O NUnder the action of cyclic loading, many factors, which are generally coupled with each other, may affect fatigue damage evolution in metals. 1-13 Therefore, a satisfactory theory with sound physical reasoning should be estabCorrespondence: Sun Binxiang.

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