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Licensed Unlicensed Requires Authentication Published by De Gruyter June 22, 2016

Combined Hot Isostatic Pressing and Heat Treatment of Aluminum A356 Cast Alloys*

Heißisostatisches Pressen von Aluminiumgusslegierungen mit integrierter Wärmebehandlung
  • S. Hafenstein , M. Brummer , M. Ahlfors and E. Werner

Abstract

The mechanical and microstructural properties of aluminum A356 cast alloy are investigated as a function of hot isostatic pressing and heat treatment parameters. The combined hot isostatic pressing and heat treatment process leads to an improvement of mechanical properties when compared to regular hot isostatic pressing with no separate heat treatment. An oversaturated state with magnesium and silicon atoms dissolved in the aluminum matrix can be achieved by increasing the quenching rate to 6.9 K/s within the temperature range between 813 K and 473 K. Aging can be performed directly after hot isostatic pressing, without the necessity of a separate solution annealing step. Thereby, the overall processing costs could be reduced.

Kurzfassung

Die Forschungsarbeit zeigt die Möglichkeit auf, heißisostatisches Pressen und Lösungsglühen in einem Prozessschritt zu realisieren. Mit dem Gebrauch einer neuartigen Schnellkühlung integriert in einer heißisostatischen Presse konnten beim Absenken der Temperatur von 813 K auf 473 K Abschreckraten von bis zu 6,9 K/s erreicht werden. Die mikrostrukturelle sowie die mechanische Werkstoffcharakterisierung belegen eine mit dem Prozessschritt des heißisostatischen Pressens erreichte Einstellung eines übersättigten Mischkristalls. Die Auslagerungsbehandlung kann somit unmittelbar nach dem heißisostatischen Pressen ohne zusätzliches Lösungsglühen durchgeführt werden. Dadurch könnten die gesamten Herstellkosten gesenkt werden.


*

Lecture held by Stephan Hafenstein at the HK2015, 71st HeatTreatmentCongress, October 28–30, 2015, in Cologne.

5 (Corresponding author/Kontakt)

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Published Online: 2016-06-22
Published in Print: 2016-06-15

© 2016, Carl Hanser Verlag, München

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