Unlike natural gas, hydrogen gas in contact with material surfaces liberates atomic hydrogen, which can dissolve into the material and alter important properties such as deformation and fracture behavior. Under the sponsorship of the Department of Energy's Hydrogen, Fuel Cells & Infrastructure Technologies program, Sandia is leading an effort to develop a technical reference for use by the various U.S. agencies involved in developing codes and standards, as well as by companies involved in developing and supplying hydrogen-related products. This database will serve as a central point of reference for technical data on the behavior of a variety of materials upon interaction with hydrogen gas.

The Technical Reference for Hydrogen Compatibility of Materials is a living document containing data obtained from public sources and also demonstrates areas requiring additional research and testing. Sandia is collaborating with industry and various codes and standards agencies, such as the Department of Transportation, the American Society of Mechanical Engineers, and the National Fire Protection Association, in assembling the reference. To launch the effort, Sandia hosted a workshop for representatives from interested parties in December 2003. The findings from this workshop as well as interactions with the codes and standards agencies are being used to guide materials testing programs at Sandia.

Sandia has a number of facilities for characterizing hydrogen effects on materials located at its Livermore, Calif., site:

• Two stations for exposing mechanical test specimens to high-pressure hydrogen gas. Each station consists of one or two A-286 stainless steel pressure vessels that fit into a furnace, which allows hydrogen exposures up to 20 ksi (138 MPa) pressure at 300°C. This capability is used in conjunction with other mechanical test equipment to examine the effects of internal hydrogen on the properties of materials.
• Five stations for measuring hydrogen-assisted crack growth rates and threshold stress intensity factors in high-pressure hydrogen gas at 25°C. Each station consists of an A-286 pressure vessel that can accommodate eight statically loaded crack-growth specimens. These experiments are conducted in hydrogen gas at pressures up to 28.8 ksi (199 MPa).
• One station for measuring hydrogen-assisted crack growth rates and threshold stress intensity factors in high-pressure hydrogen gas at temperatures ranging from -70°C to 170°C. The station consists of an A-286 pressure vessel that fits into a custom-designed temperature chamber. Eight statically loaded crack growth specimens can be tested in hydrogen gas at pressures up to 28.8 ksi (199 MPa).

Contact:
Brian Somerday
bpsomer@sandia.gov
(925) 294-3141

Chris San Marchi
cwsanma@sandia.gov
(925) 294-4880