Session: MF-02-09 Pipeline Infrastructure 2

Paper Number: 122754

122754 - Fracture and Fatigue Properties of High Strength Ferritic Steels Welds in High Pressure Hydrogen 

High strength ferritic steels are ubiquitously used for construction of pressure vessels for hydrogen storage and transportation, thanks to the combination of affordable cost and availability of material for construction. As hydrogen grows in popularity as a carbon-neutral energy vector, the number and size of installations for hydrogen storage are expected to grow, and large vessels fabricated by welding are among the possible solutions to meet this increasing demand of storage capacity.

Ferritic steels suffer from hydrogen assisted cracking, and therefore safe design requires reliable knowledge of their fracture and fatigue properties when exposed to pressurized hydrogen environment. Thankfully, this information is today available for most commonly used steel grades [1, 2].

However, these known design curves are specific for wrought products, whose microstructure is achieved by precise heat treatment conditions, typically, quenching and tempering. Welding however inevitably produces a local transformation of the material’s microstructure, and a gradient of properties in the volume surrounding the solidified pool. Therefore, fabricating any high strength steel pressure equipment that includes welds requires characterization of the fracture and fatigue properties of the different microstructural regions.

Previous work from the same authors [3] demonstrated the variable performance of high strength steel welds in gaseous hydrogen, and thus the effect of welding parameters. This paper expands the previously published information, presenting new experimental findings from the characterization of welds manufactured from different high strength steel formulations, and discusses the effect of chemical composition on the fracture properties of these welds in pressurized hydrogen.

 

[1] ASME BPVC Code Case 2938-latest revision.

[1] ASME B31 Code Case 220-latest revision.

[3] P. Bortot, M. Ortolani, M. Sileo, E. Escorza, M. Connolly, Z. Buck, A. Chandra. Welding high strength ferritic steels for hydrogen service. International Hydrogen Conference, 2023.

Presenting Author: Matteo Ortolani Tenaris

Presenting Author Biography: Working as metallurgist at Tenaris since 2011, M. has been involved with steel design and manufacturing process optimization of seamless tubular products for a variety of industrial applications, including power & process plants, structural and mechanical pipes, automotive products, tubular products and pressure vessels for high pressure hydrogen storage and transportation.
Currently, M. is responsible for the engineering and development of tubular products for boiler and pressure vessels at Tenaris.
M. is member of the ASME Boiler and Pressure Vessels Code Standards Committee on Materials (BPV II) and Power Boilers (BPV I).

Authors:

Matteo Ortolani Tenaris
Paolo Bortot Tenaris
Matthew Connolly NIST
Zack Buck NIST