Hydrogen compatibility of structural materials for energy-related applications

Structural materials for H pressure vessels and H pipelines are discussed along with processes for producing H from water. The most difficult problems of those discussed are related to the design and construction of pressure vessels and pipelines for high pressure hydrogen. Because of the size of the facilities, quality control is difficult and low-cost materials must be used. In underground pipelines, the problems are compounded by possible corrosive attack leading to crack formation. In hydride storage vessels, the hydrogen pressures are sufficiently low that ordinary steels can be used as long as the design is conservative or special design features are incorporated. In thermochemical hydrogen production processes, the combined effects of hydrogen and corrosive halogens need to be investigated. Combined effects of hydrogen, other gases, and abrasive solids are the main concern in coal conversion processes. In all applications, there does not appear to be a critical need for new alloy development to protect against hydrogen damage, although the development of lower cost alloys or alloys with better properties should not be discouraged. Also, commercially available alloys may be inadequate for applications in which hydrogen damage is not the only concern