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Microstructural and Fractographical Studies on Quenched and Tempered Armor Steels

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Published/Copyright: May 26, 2013
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Materials Testing
From the journal Materials Testing Volume 52 Issue 5

Abstract

In this study, a boron-alloyed experimental steel has been rolled to form a sheet product, and an austenization treatment has been performed, followed by rapid quenching and then tempering. By austenization, a homogeneous austenite phase is obtained and a martensitic microstructure is formed after rapid quenching. This kind of microstructure exhibits high hardness, but low toughness. Thus, a tempering heat treatment is applied at a proper temperature (200 °C and 600 °C) and various times, in order to provide optimum toughness and to develop an ideal combination of strength and toughness.

After this process, at first the phases formed during the equilibrium state have been studied for the alloy system using ThermoCalc data, and also their amounts have been evaluated. The microstructures acquired after the heat treatments have been examined by light microscopy. The effects of the formed microstructures on mechanical properties are comparatively given by their strength, toughness, and elongation values. Furthermore, the failure mechanism with fractografical examinations has been determined by using a Scanning Electron Microscope (SEM).

Kurzfassung

Die diesem Beitrag zugrunde liegende Studie befasst sich mit experimentellen Bor-legierten Stählen, die nach dem Walzen austenitisiert, abgeschreckt und angelassen sind. Bei der Austenitisierung hat sich eine homogene Austenitphase eingestellt, die nach dem Abschrecken vollständig in Martensit umwandelt ist. Dieses Gefüge ist sehr hart, jedoch ist seine Zähigkeit niedrig. Deshalb ist eine Anlass-Wärmebehandlung bei 200 °C und 600 °C und unterschiedlichen Zeiten durchgeführt worden, um eine optimale Zähigkeit und damit eine ideale Kombination von Festigkeit und Zähigkeit zu erhalten.

Die Phasen, die sich bei der Abkühlung der gegebenen Stahlzusammensetzung bilden, sowie ihre Mengen wurden für den Gleichgewichtszustand mittels ThermoCalc bestimmt. Die verschiedenen Wärmebehandlungsgefüge sind mit dem Lichtmikroskop untersucht worden. Der Einfluss der Gefüge auf die mechanischen Eigenschaften sind durch den Vergleich ihrer Festigkeit, Dehnung und Schlagzähigkeit angegeben worden. Darüber hinaus sind die Bruchflächen der Proben für den Zugversuch und Schlagbiegeversuch mit dem Rasterelektronenmikroskop untersucht worden, um die Bruchmechanismen zu ermitteln.

Prof. Dr. Sadi Karagöz, born in Bolu-Turkey, graduated as M.Sc. at the Montanuniversität in Leoben, Austria, where he achieved also his doctoral degree. He worked as guest scientist at Max Planck Institute for Metal Research in Stutgart. In 1984 he joined Yildiz University in Istanbul, Turkey. In 1993 he went to Kocaeli University, Izmit, Turkey to build up the Department of Metallurgical and Materials Engineering where he was the head. He is now working at the Marmara University, Technology Faculty, Mechatronics Department, Istanbul.

Dipl.-lng. Hakan Atapek, born in Adana, graduated from the Kocaeli University Izmit, Department of Metallurgical and Materials Engineering in 2003. He received his M.Sc. degree from the Kocaeli University, Izmit, in the same Department. He has been working in Kocaeli University Izmit Dept. of Metallurgical and Materials Engineering since 2003.

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 the 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.

References

1 R.Davis, K. M.Mills, S.Lampman, T. B.Zorc: Properties and Selection: Irons, Steels and High-Performance Alloys, ASM Handbook, Vol.1, Materials Park, Ohio, USA (1991Search in Google Scholar

2 Atapek: Development an Armor Steel Along the Principles of Physical Metallurgy & Its Characterization, M.Sc Thesis, Institue of Natural and Applied Sciences, Kocaeli University (2006)Search in Google Scholar

3 Smoljan: Prediction of mechanical properties and microstructure distribution of quenched and tempered steel shaft, Journal of Materials Processing Technology, 175 (2006), pp. 393–39710.1016/j.jmatprotec.2005.04.068Search in Google Scholar

4 Karagöz, A. Yılmaz, H.Atapek: Armor Steels and their Development, Proc. of the 3th National Defence Technologies Congress, METU, Ankara (2006), pp. 501–511Search in Google Scholar

5 Matsubara, T. Osuka, I.Kozasu, K.Tsukada: Optimization of metallurgical factors for production of high strength, high toughness steel plate by controlled rolling, Transactions ISIJ12 (1972), pp. 435–443Search in Google Scholar

6 Mills, J. R. Davis, J. D.Destefani: Fractography, ASM Handbook, Vol. 12, Materials Park, Ohio, USASearch in Google Scholar

7 W.Honeycombe: Steels – Microstructure and Properties, Metallurgy and Materials Science Series, UK (1981)Search in Google Scholar

8 Karagöz, A. Y lmaz, H.Atapek: Development of quenched and tempered sheet steel products, Proc. of the 13th International Metallurgy & Materials Congress, Abstract book, Istanbul (2006), p. 64Search in Google Scholar

9 Karagöz, H.-O. Andren: Secondary hardening in high speed steels, Z. f. Metallkunde83 (1992), pp. 386–394Search in Google Scholar

10 Fischmeister, S. Karagöz, H.-O.Andren: An atome probe study of secondary hardening in high speed steels, Acta Metall.36 (1988), pp. 817–82510.1016/0001-6160(88)90136-8Search in Google Scholar

11 Karagöz, H. Fischmeister, H. -O.Andren, H.-O.,Jun, Cai-Guang: Microstructural changes during overtempering of high speed tool steels, Metall. Trans., 23A (1992), pp. 1631–1640Search in Google Scholar

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

© 2010, Carl Hanser Verlag, München

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  8. Microstructural and Fractographical Studies on Quenched and Tempered Armor Steels
  9. Hydro-Abrasive Erosion Resistance of C45 Steel in Different Heat-Treated States on a Designed Wear Test Apparatus
  10. A new approach to the kinematic analysis of universal joints
  11. Vorschau/Preview
  12. Vorschau
https://doi.org/10.3139/120.110134

Articles in the same Issue

  1. Inhalt/Contents
  2. Inhalt
  3. Fachbeiträge/Technical Contributions
  4. Ein verbessertes Verfahren zur Lebensdauerabschätzung mittels linearer Schadensakkumulation
  5. Ein Sensorkonzept auf der Basis piezoelektrischer PVDF-Folien zur Messung bruchmechanischer Beanspruchungsgrößen
  6. Parametric (Non)-Variance of the Mid-Regime Fatigue Crack Propagation in an Aluminium Alloy AA6056-T6
  7. Effects of Shielding with Various Hydrogen-Argon Mixtures on Supermartensitic Stainless Steel TIG Welds
  8. Microstructural and Fractographical Studies on Quenched and Tempered Armor Steels
  9. Hydro-Abrasive Erosion Resistance of C45 Steel in Different Heat-Treated States on a Designed Wear Test Apparatus
  10. A new approach to the kinematic analysis of universal joints
  11. Vorschau/Preview
  12. Vorschau
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