Accessible Requires Authentication Published by De Gruyter May 26, 2013

Development of an Armor Steel for Ballistic Protection

Entwicklung eines Panzerstahles für ballistischen Schutz
Alpay Yilmaz
From the journal Materials Testing

Abstract

In this study, a newly developed Boron alloyed armor steel is presented and its mechanical properties as well as its ballistic applications are given. Further, a description of ballistic terms is included to understand the development of armor steel for the use in civil and defence applications. The main subject of the study is the microstructural design of these steels. For this purpose a Boron alloyed experimental steel has been produced by quenching and tempering. The microstructures obtained after such heat treatments have been examined by light microscopy (LM) and scanning electron micoscopy (SEM). The application of precipitation hardening is highlighted by the effect of alloying elements and the resulting matrix hardening potential. As a result, a suggestion is given for the alloy design of the new armor steel with Boron additions. The effect of microstructure and mechanical properties (strength, hardness, toughness, etc.) of this experimental armor steel have been evaluated by methods similar to homogeneous rolled armor steels (MIL-A-12560) targeted at a good ballistic performance. Also the effect of heat treatment on the mechanical properties of armor steel is shown. The impact toughness values at different test temperatures are comparatively given in addition to the relationship between ballistic performance and hardness for armor steels. Attempts have been undertaken to explain the cause of deformation and failure occurred in the steel plates due to projectile penetration with light and scanning electron microscopical studies.

Kurzfassung

Im vorliegenden Beitrag wird ein kürzlich entwickelter Bor-legierter Panzerstahl mit seinen mechanischen und ballistischen Eigenschaften vorgestellt. Darüber hinaus werden die ballistischen Anforderungen beschrieben, um die Entwicklung des Stahles für die Nutzung im zivilen und militärischen Bereich besser zu verstehen. Das Hauptthema dieses Beitrages ist die mikrostrukturelle Auslegung dieses Stahles. Zu diesem Zweck wurde eine Bor-legierte Versuchscharge abgeschreckt und angelassen. Das Gefüge nach solchen Wärmebehandlungen wurde mittels Lichtmikroskopie und Rasterlektronenmikroskopie untersucht. Die angewendete Ausscheidungshärtung wird anhand der Wirkung der Legierungselemente und dem resultierenden Aufhärtungseffekt vorgestellt. Als ein Ergebnis werden Vorschläge für das Legierungskonzept dieses neuen Panzerstahles mit Borzugaben gemacht.

Die Auswirkungen des Gefüges und der mechanischen Eigenschaften (Festigkeit, Härte, Zähigkeit etc.) dieses experimentellen Panzerstahles wurden mit ähnlichen Verfahren evaluiert, wie für gewalzte Panzerstähle (MIL-A-12560), um ein gutes ballistisches Verhalten zu erzielen. Außerdem wird die Wirkung der Wärmebehandlung auf die mechanischen Eigenschaften dargestellt. Die Zähigkeitskennwerte für die verschiedenen Prüftemperaturen wurde vergleichsweise angegeben, ergänzend zum Verhältnis zwischen ballistischem Verhalten und Härte. Die Ursachen für die Deformation und das Versagen der Stahlplatten infolge Durchschusses mittels Licht- und Rasterelektronenmikroskopie werden beleuchtet.


Dr.-Ing. Alpay Yilmaz, Jahrgang 1973, achieved his Bachelor Degree at the Technical University of Istanbul in 1996, his MSc degree at the Kocaeli University in 2002 and his Dr.-Ing degree at Kocaeli University in 2006. From 1996 to 1998 he was working in the Foundary Anadolu Döküm. Then he changed to the Turkish Army and was head of the Departments Foundary and Heat Treatment at the 7th Maintenance Center in Tuzla, Istanbul, from 1998 to 2007. Since 2007, he is at the Turkish Land Forces Command, Office of Technical Project & Administration in Ankara, Turkey.


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Published Online: 2013-05-26
Published in Print: 2010-11-01

© 2010, Carl Hanser Verlag, München