Hot deformation of an Al–Cu–Mg powder metallurgy alloy

The effort to improve automobile efficiency has potential economic and environmental advantages. The field of aluminum powder metallurgy (P/M) is of particular interest as the implementation of such technologies to produce parts can offer the combination of a weight savings and the economic advantages of near net shape processing. However, one of the hurdles to overcome in the field of P/M is the presence of porosity in the sintered product. To reduce the presence of this attribute, sintered materials can be hot forged to full density. In this study, the forging response of a novel aluminum–copper–magnesium P/M alloy, P/M 2324, was studied in comparison to its wrought counterpart AA2024. Modelling of the peak flow stress required in the P/M and wrought alloys yielded very similar results with both materials adhering to a standard Zener–Hollomon curve fitting approach. Rotary swaging was also completed to assess the impact of hot work on the P/M material. These findings confirmed that full density could be achieved in P/M 2324 and that the concomitant tensile properties were significantly higher for the swaged P/M system. Microstructurally, it appeared that the principal secondary phase in P/M 2324 was θ (Al2Cu) whereas the S phase (Al2MgCu) was pronounced in the wrought system.

► The hot forging response of P/M and wrought versions of 2024 were studied.
► All materials strongly adhered to a standard Zener–Hollomon model.
► It was confirmed that full density was achieved in P/M 2324 through hot working.
► Hot worked P/M 2324 exhibited a yield strength of 386 MPa and a UTS of 448 MPa.
► The tensile properties of hot worked P/M 2324 exceeded those of wrought 2024.