A defect-based fatigue life estimation method for laser additive manufactured Ti-6Al-4V alloy at elevated temperature in very high cycle regime

The application of Laser additive manufactured Ti-6Al-4V alloy in aeroengine industry requires feasible life prediction methods at the service temperature. The very high cycle fatigue tests are conducted for a laser additive manufactured Ti-6Al-4V alloy, and the effects of building direction, temperature, and defect size are discussed. To establish a simple and accurate life prediction method, this study links defect area to fatigue life. The information of defect location, size, and morphology are integrated in a parameter reflecting the stress around defect, which is applied in modified Steuer's model. The prediction results are with an accuracy of factor two.