Influence of Martensitic Phase on Microcrack Propagation in a Ferritic-Martensitic Steel

Abstract:

Hard phases such as martensite regions affect micro-crack extension by blocking the plastic zone ahead of the crack tip, but also by changing the crack opening which can be taken as loading quantity for cracks. This paper deals with the measurement of crack opening for microcracks in a ferrite/martensite dual phase steel. The methods used are in-situ testing in the SEM, X-ray tomography, and digital image correlation. It was found that martensite regions affect the relative displacement of the crack phases both at the crack tip and in the crack wake.

• Periodical: Advanced Materials Research (Volumes 891-892)
• Pages: 301-306
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.891-892.301
• Online since: March 2014
• Authors: Angelika Brueckner-Foit*, Pascal Pitz, Frank Zeismann, Lisa Zellmer
• Keywords: Crack Opening Displacement, Digital Image Correlation (DIC), Dual Phase Steel, Microcrack, X-Ray Tomography

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