Age Hardening of Forged Aluminium Components – Mechanical Properties and Distortion Behaviour after Gas Quenching
For quenching of age hardenable aluminum alloys today predominantly aqueous quenching media are used, which can lead due to the Leidenfrost phenomenon to a non-uniform cooling of the parts and thus to distortion. In relation to the conventional quenching procedures in aqueous media, gas quenching exhibits a number of technological, ecological, and economical advantages. The quenching intensity can be adjusted by the variable parameters gas pressure, gas velocity as well as the kind of gas and thus can be adapted to the requirements of the component. By the higher uniformity and the better reproducibility, gas quenching offers a high potential to reduce distortion. Cost savings would be possible, because of reduced distortion and therefore less reworking. High-pressure gas quenching with nitrogen or helium, as well as air quenching at ambient pressure in a gas nozzle field was applied to the spray formed aluminum alloy Al-17Si-4Fe-3Cu-0.5Mg-0.4Zr (DISPAL S232). Hardness and tensile tests have been carried out to determine the mechanical properties after gas quenching and aging compared to water quenching. The distortion behavior of a forged aluminum component of the spray formed alloy was examined after gas quenching and after water quenching. Gas quenching showed remarkable advantages regarding distortion.
W.J. Poole, M.A. Wells and D.J. Lloyd
A. Rose, O. Kessler, F. Hoffmann, H.W. Zoch, P. Krug, "Age Hardening of Forged Aluminium Components – Mechanical Properties and Distortion Behaviour after Gas Quenching", Materials Science Forum, Vols. 519-521, pp. 383-388, 2006