Analysis of isothermal forging process and mechanical properties of complex aluminum forging for aviation

Abstract

Large complex 7A85 aluminum wing-body joint was forged employing isothermal forging process and its mechanical properties were studied. The tensile strength after forging is up to 587.5 MPa in longitudinal direction, 15% higher than that using free forging. Moreover, the tensile strength of the forging is almost the same in three directions. Isothermal forging also performs well on overall fracture toughness, with a maximum value of 39.8 MPa·m^1/2, and that of short transverse direction all reaches 36 MPa·m^1/2 and above, with a maximum relative error of only 3.6%. The results indicate that the isothermal forging leads to better performance as well as higher uniformity in mechanical properties.

Keywords

aviation forging / isothermal forging process / uniformity / fracture toughness

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