Abstract Scope |
High pressure cold spray was utilized to deposit F357 aluminum powders E357 cast substrates in relevant repair geometries using both helium and nitrogen processing conditions. Materials were analyzed using cross-sectional microscopy, microhardness analysis, and static and dynamic mechanical testing. The nitrogen and helium conditions resulted in tensile strengths of 21 and 43 ksi, respectively. The nitrogen condition exhibited brittle behavior, whereas the helium condition exhibited 3.5% elongation. Fatigue results indicated that both nitrogen and helium conditions provided significant fatigue benefit at loads below the tensile strength of the material. At higher loads, the nitrogen condition provided a fatigue debit, where the helium condition maintained near-pristine properties. We will further show that by improving the static strength of the nitrogen condition, the fatigue debit is eliminated for the high loading condition, indicating that the dynamic properties of the cold spray repair are closely related to the material strength. |