Abstract: To be updated

Abstract: The scatter of the fatigue life of additive manufacturing specimens is quite large because of the defects dispersed in material. Due to the various defects and the large life scatter of additive manufacturing material, the relationship between life and defect characterization parameters such as defect type, defect location, and defect size are complex. This paper analyses the effect of defects on fatigue life from the perspective of statistical sense. The statistical results based on both the minimum life of the samples under the same stress level and the half of the samples with the fatigue life less than the median show that the defect size has a great influence on the fatigue life. However, the "effective area", i.e., the projection area of a defect on the plane vertical the loading direction, is not an ideal parameter to characterize the defect. In other word, the sample with the maximum defect in term of the effective area is not necessarily the shortest life sample. Fatigue life is more sensitive to the defects on surface or near-surface than those inside a specimen. There is little difference in the hazards of the two types of defects to fatigue performance, porosity defect induced failure is slightly higher than non-fusion defect induced failure.

Keywords: Additive manufacturing material, defects, defect size, defect location, fatigue life.