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Licensed Unlicensed Requires Authentication Published by De Gruyter December 22, 2014

Shot Peening Induced Plastic Deformation in Cast Iron – Influence of Graphite Morphology*

Plastische Verformung durch Kugelstrahlen von Gusseisen – Einfluss der Graphit-Morphologie
M. Lundberg, R. L. Peng, M. Ahmad, D. Bäckström, T. Vuoristo and S. Johansson

Abstract

Graphite morphology in cast iron strongly affects the mechanical properties such as: Young's modulus, tensile/compressive strength and cyclic mechanical behaviour. In this study, pearlitic compact graphite iron (CGI) and grey cast iron (GI) have been studied in a scanning electron microscope (SEM) before and after shot peening under different conditions. The plastic deformation behaviour of CGI and GI under different shot peening conditions has been analysed using electron backscattering diffraction (EBSD) and electron contrast channelling imaging (ECCI). EBSD and ECCI revealed that plastic deformation around graphite inclusions depends on the size and shape of the graphite. The different response of CGI and GI to shot peening is explained by the different damping properties of the graphite and the matrix capability for plastic deformation. n

Kurzfassung

Die Graphitmorphologie in Gusseisen hat einen starken Einfluss auf die mechanischen Eigenschaften wie E-Modul, Zug- und Druckfestigkeit und das Verhalten unter zyklischer Belastung. Für diese Arbeit wurden Proben aus Grauguss und Vermiculargraphitguss vor und nach einer Kugelstrahlbehandlung mit unterschiedlichen Parametern im Rasterelektronenmikroskop untersucht. Die plastische Verformung wurde mittels EBSD und ECCI analysiert. Dabei zeigt sich, dass die plastische Verformung in der Umgebung von Graphiteinschlüssen von Form und Größe der Einschlüsse abhängt. Die unterschiedlichen Effekte in Grauguss und Vermiculargraphitguss lassen sich mit den verschiedenen Dämpfungseigenschaften der jeweiligen Graphite und der Duktilität der Matrix erklären. n


4 (Corresponding author/Kontakt)
*

Enhanced contribution based upon a presentation at the International Conference on Residual Stresses ICRS9, October 7–9, 2012, in Garmisch-Partenkirchen, Germany


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Online erschienen: 2014-12-22
Erschienen im Druck: 2014-04-30

© 2014, Carl Hanser Verlag, München

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