| Abstract Scope |
During the production of the 7xxx-series of aluminum alloys employed in the aerospace industry, cast ingots experience high levels of mechanical stresses, which can result in cold cracking after solidification. While cold cracking is attributed to brittle phases in the as-cast structure, the presence of hydrogen in the alloy and water on the surface of these ingots suggests that hydrogen embrittlement may play a role.
As-cast 7xxx Al samples from cold-cracked and non-cold cracked ingots were tested for both tensile and fracture toughness properties. For comparison, additional samples were exposed to 100 °C water to promote hydrogen evolution, then tested within two hours of exposure to minimize hydrogen diffusion out of the matrix. The as-cast samples demonstrated a combination of brittle and ductile fracture, with brittle fracture following secondary phases. The impact of hydrogen exposure on ductility and fracture toughness will be explored. |