Speaker
Description
Positron Annihilation Lifetime Spectroscopy (PALS) is a unique tool for studying precipitation hardening in Al alloys, utilizing the tendency of positrons to get trapped in Cu clusters/precipitates.
Alloying AlCu with Ag has been shown to leverage the formation of the so-called Ω-phase, known for its particularly high strength and thermal stability.
After discussing optimal Al-alloy surface treatments for positron annihilation spectroscopy, we present PALS measurements of AlCu4Mg0.3Ag0.7 containing Ω-phase precipitation after hot-rolling and subsequent T4-treatment.
Our measurements showcase the high thermal stability of the Ω-phase and can be used to optimize process parameters of the strength hardening and the temperature treatment.
All data presented have been recorded at the SLOPE facility at TUM [1] and the ELBE facility at HZDR [2].
[1] L. Mathes, M. Suhr, V. V. Burwitz, D. R. Russell, S. Vohburger, and C. Hugenschmidt, "Surface and near-surface positron annihilation spectroscopy at very low positron energy," arXiv preprint, arXiv:2409.07952, Sep. 2024.
[2] A. Wagner, M. Butterling, M.O. Liedke, K. Protzger, R. Krause-Rehberg, "Positron annihilation lifetime and Doppler broadening spectroscopy at the ELBE facility," AIP Conference Proceedings 1970, 2018.
