Ultrasonic peening treatment used to improve stress corrosion resistance of AlSi10Mg components fabricated using selective laser melting

Abstract

As a rapidly evolving advanced digital manufacturing technology, additive manufacturing (AM) has its advantages including short manufacturing cycle, material saving, and complexity for free. It has great potential for application in marine and offshore engineering. However, stress corrosion damage will be a big threat for the additively manufactured metal parts in the ocean environment due to large residual stresses generated in the building process. This paper focuses on the effect of ultrasonic peening treatment (UPT) on stress corrosion resistance of AlSi10Mg components fabricated using Selective Laser Melting (SLM). Firstly, AlSi10Mg specimens were prepared using an SLM machine, and UPT was conducted on the specimen’s top surface. Then, a series of measurements and analyses were carried out for the specimens before and after the UPT process. The residual stresses and hardness of the specimens were measured, and the surface morphology was observed using a scanning electron microscope (SEM). The resistance of stress corrosion was evaluated by the electrochemical corrosion test. The experimental results show that UPT can significantly improve stress corrosion resistance of SLM-fabricated specimens.