Abstract

The main objective of the study is as follows: Identify steel compositions/microstructures suitable for construction of new pipeline infrastructure and evaluate the potential use of the existing steel pipeline infrastructure in high pressure gaseous hydrogen applications. The microstructures of four pipeline steels were characterized and tensile testing was conducted in gaseous hydrogen and helium at pressures of 5.5 MPa (800 psi), 11 MPa (1600 psi) and 20.7 MPa (3000 psi). Based on reduction of area, two of the four steels that performed the best across the pressure range were selected for evaluation of fracture and fatigue performance in gaseous hydrogen at 5.5 MPa (800 psi) and 20.7 MPa (3000 psi). The basic format for this phase of the study is as follows: Microstructural characterization of volume fraction of phases in each alloy; Tensile testing of all four alloys in He and H{sub 2} at 5.5 MPa (800 psi), 11 MPa (1600 psi), and 20.7 MPa (3000 psi). RA performance was used to choose the two best performers for further mechanical property evaluation; Fracture testing (ASTM E1820) of two best tensile test performers in H{sub 2} at 5.5 MPa (800 psi) and 20.7 MPa (3000 psi); Fatigue testing (ASTM E647) ofmore » two best tensile test performers in H2 at 5.5 MPa (800 psi) and 20.7 MPa (3000 psi) with frequency =1.0 Hz and R-ratio=0.5 and 0.1.« le Document type: Report