The efficiency of tumble finishing as a final post-treatment for fatigue enhancement of notched laser powder bed fusion AlSi10Mg

Erfan Maleki; Sara Bagherifard; Okan Unal; Manoj Revuru; Michele Bandini; Mario Guagliano

doi:10.1038/s41598-023-30660-6

The efficiency of tumble finishing as a final post-treatment for fatigue enhancement of notched laser powder bed fusion AlSi10Mg

Sci Rep. 2023 Mar 21;13(1):4602. doi: 10.1038/s41598-023-30660-6.

Authors

Erfan Maleki¹, Sara Bagherifard², Okan Unal³, Manoj Revuru¹, Michele Bandini⁴, Mario Guagliano¹

Affiliations

¹ Department of Mechanical Engineering, Politecnico di Milano, Milan, Italy.
² Department of Mechanical Engineering, Politecnico di Milano, Milan, Italy. sara.bagherifard@polimi.it.
³ Department of Mechanical Engineering, Karabuk University, Karabuk, Turkey.
⁴ Peen Service Srl, Bologna, Italy.

Abstract

A hybrid post-treatment combining tumble finishing as a final step after shot peening and heat treatment was developed to alleviate the adverse effects of internal and surface defects on the fatigue performance of laser powder bed fusion AlSi10Mg samples. The effects of each post-treatment were investigated individually and synergistically on microstructure, surface morphology and roughness, hardness, residual stresses, porosity, and rotating bending fatigue behavior of V-notched AlSi10Mg samples. The results reveal that tumble finishing can highly reduce surface roughness by 28 and 32% compared to the as-built and heat-treated states while inducing extra surface layer hardening and compressive residual stresses. The hybrid post-treatment of heat treatment + shot peening + tumble finishing significantly increased the fatigue life of the samples by over 500 times higher compared to the as-built series.