Low cycle fatigue of additively manufactured thin-walled stainless steel 316L
Journal article, 2021

To ensure the robust design freedom of metallic additive manufacturing, the fatigue properties and the dimensional limitation of as-built components by laser powder bed fusion (PBF-LB) are investigated. Fully reversed and strain-controlled fatigue tests were carried out on tubular specimens with different wall thicknesses, 1 mm and 2 mm, for the purpose of studying the thin-wall effect without having risk of buckling problem during compression. Two wrought conditions are also enclosed as a comparison, which are the cold worked (CW) and solution annealed condition (SA). In the as-built PBF-LB tubular specimens, deformed microstructure and deformation twins are discovered close to the surface region, together with a higher roughness of the inner surface due to the heat accumulation. The surface roughness is evaluated as micro-notches, and a higher fatigue notch factor, Kf, at lower applied strain range is revealed. The factors influencing Kf include, the non-conductive inclusions serving as crack initiation sites at the surface region, and the deformation twins formed by the local stress concentration. The strain-life of PBF-LB samples is comparable with the wrought samples. However, the fatigue strength of the responding mid-life stress shows greater difference and is in the following order, CW wrought > PBF-LB > SA wrought. Secondary cyclic hardening owing to deformation induced martensitic transformation is found in both of the wrought samples. Yet, only cyclic softening exhibits in the PBF-LB samples, which is the result of the suppressed martensitic transformation and the dislocation unpinning from the cell boundaries.


Fatigue notch factor

Deformation twinning


Martensitic transformation

Laser powder bed fusion

Surface roughness


C. H. Yu

Linköping University

Alexander Leicht

Chalmers, Industrial and Materials Science, Materials and manufacture

Ru Lin Peng

Linköping University

JJ Moverare

Linköping University

Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing

0921-5093 (ISSN)

Vol. 821 141598

Subject Categories

Applied Mechanics

Manufacturing, Surface and Joining Technology

Other Materials Engineering



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7/2/2021 8