Ultra-high Cycle Fatigue Life Prediction Considering Loading Frequency
Ultra-high cycle fatigue experiments can be conducted using traditional testing methods such as electromagnetic vibration(30-3000 Hz)and ultrasonic vibration(20 kHz).Differences in fatigue life for the same material may arise when tested under varying loading frequencies.To fully utilize the ul-tra-high cycle fatigue life data obtained from different testing systems,the impact of loading frequency on the ultra-high cycle fatigue life of materials needs to be studied imperatively.This paper presents novel prediction models for ultra-high cycle fatigue life,taking into account loading frequency.The models in-corporate the crack initiation life prediction model based on Tanaka's dislocation theory and the Paris crack growth life prediction model.The influence of loading frequency is integrated into effective stress and fa-tigue strength.The proposed models are verified using available very high cycle fatigue test data for titani-um alloy TC17 and nickel-based superalloy GH4169 under different loading frequencies.The results show that the models proposed in this work can reasonably characterize the ultra-high cycle fatigue test data of materials under varying loading frequencies,establishing the correlation of fatigue life data under different loading frequencies.
loading frequencyvery high cycle fatiguelife prediction
万方数据
维普
