Hydrogen Compatibility of Two Commercial Copper Alloys with Respect to Embrittlement

Handling hydrogen-rich atmospheres requires materials that do not deteriorate in the presence of hydrogen and that ensure safe operation. Often high strength metallic materials, however, may show catastrophic mechanical failure in the presence of hydrogen. This phenomenon, called hydrogen embrittlement, can be very dangerous, as these failures occur in a time-delayed and sudden manner. Two commercially available materials, AMPCOLOY® 83, a copper beryllium alloy, and AMPCO® 18, an aluminum bronze, have been investigated to clarify their susceptibility to hydrogen embrittlement. Hydrogen permeation measurements were performed to assess diffusivity in the materials, and hydrogen content was analyzed by thermal desorption analysis (TDA) after electrochemical charging. Mechanical properties in hydrogen-affected state were assessed by slow strain rate tensile tests (SSRT), with in situ electrochemical charging and post-test fractographic inspection of the fracture surfaces. While the aluminum bronze showed no noticeable hydrogen-related deterioration, copper beryllium alloy experienced some embrittlement, however, having a low fracture strain even in the uncharged state.