Abstract
Hydrogen embrittlement (HE) decreases the mechanical properties of steels, even in those with favourable mechanical properties and corrosion resistance as duplex stainless steels (DSS). This effect can limit the use of DSS for hydrogen storage and transport. This work studies HE in a 2205 duplex stainless steel obtained by Selective Laser Melting (SLM) additive manufacturing.
The hydrogen embrittlement behaviour was assessed through in-situ fracture testing using single-edge notched bend specimens (SE(B)) in two environments: gaseous and electrochemical. For the gaseous method, high-pressure hydrogen gas at 35, 70, and 140 bar, and different test rates were employed. In the case of the electrochemical hydrogen charging, different rates were also used, but in a saline electrolyte under a constant current density of 0.5 mA/cm2. Fracture surfaces were analysed by scanning electron microscopy.
Both, mechanical results and fracture surfaces were compared with a conventional hot-rolled 2205 duplex stainless steel. This study highlights the critical role of manufacturing-induced microstructures on hydrogen-assisted fracture and establishes guidelines for the design of cost-effective and reproducible experimental methods in the study of HE.