Abstract
An attempt has been made to determine the suitability of the conventional Jominy end quench test for assessing the quenching behaviour of heat treatable aluminium alloys. Hence it was decided to apply the Jominy test initially on specimens of 6061, 2024, and 7075 alloys possessing considerable differences in quenching response.
The Jominy test with slight modification was found to be successful in revealing the quenching response of the alloys studied. Experimental results have indicated that the quench sensitivity of these alloys increases in the order of 6061, 2024, and 7075. The quench sensitivity of Al alloys is primarily governed by two factors. Firstly, the increase in the concentration of the alloying elements increases the quench sensitivity. Secondly, the elements that form high temperature intermetallics make aluminium alloys more quench sensitive.
Kurzfassung
Abschreckverhalten von Aluminiumlegierungen mit mittlerer und hoher Festigkeit. Im vorliegenden Beitrag wird über den Versuch berichtet, die Eignung des konventionellen Jominy-Abschreckversuches zur Einschätzung des Abschreckverhaltens von wärmebehandelbaren Aluminiumlegierungen zu untersuchen. Hierzu wurde zunächst entschieden, den Jominy-Versuch an Proben der Legierungen 6061, 2024 und 7075 anzuwenden, die bemerkenswerte Unterschiede in ihrem Abschreckverhalten aufweisen.
Es stellte sich heraus, dass der Jominy-Versuch mit leichter Modifizierung das Abschreckverhalten der untersuchten Legierungen wiedergibt. Die Untersuchungsergebnisse haben gezeigt, dass die Abschreckempfindlichkeit dieser Legierungen in der Reihenfolge 6061, 2024 und 7075 zunimmt. Die Abschreckempfindlichkeit von Aluminiumlegierungen wird vor allem durch zwei Faktoren bestimmt. Erstens steigt mit zunehmenden Anteilen an Legierungselementen die Abschreckempfindlichkeit. Zweitens machen die Elemente, die intermetallische Verbindungen bei hohen Temperaturen bilden, abschreckempfindlicher.
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