Phenomenological Modelling of Impact Toughness Transition Behaviour

Abstract:

The toughness transition behavior of ferritic steel results from the fact that two competing fracture mechanisms can be activated independently or progressively. Temperature, strain rate and the material ́s hardening properties are the major influences affecting the result of this competition between cleavage and ductile fracture mechanisms. An elastic visco-plastic plasticity model with stress-state dependent yielding and isotropic hardening forms the basis of a model to predict the Charpy impact toughness properties of steels with bcc crystal structure for transition behavior. A scalar damage variable is coupled into the yield potential in order to capture the effects of damage induced softening. The corresponding damage evolution law considers damage initiation criteria for both mentioned fracture mechanisms. Material parameter identifications and successful model application in terms of Charpy impact toughness tests are demonstrated.

• Periodical: Applied Mechanics and Materials (Volume 784)
• Pages: 27-34
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.784.27
• Online since: August 2015
• Authors: Sebastian Münstermann*, Pawel Kucharczyk, Georg Golisch, Benedikt Döbereiner
• Keywords: Coupling of Failure Criteria, MBW Model, Phenomenological Damage Model

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