ECCM16 - 16 TH EUROPEAN CONFERENCE ON COMPOSITE MATERIALS, Seville, Spain, 22-26 June 2014 1 MESO-SCALE ANALYSIS OF DUCTILE STEEL FABRIC/EPOXY COMPOSITES: NUMERICAL MODELLING AND EXPERIMENTAL VALIDATION J. C. Faes * , A. Rezaei, W. Van Paepegem, J. Degrieck Department of Materials Science and Engineering, Faculty of Engineering and Architecture, Ghent University, Technologiepark-Zwijnaarde 903, B-9052 Zwijnaarde, Belgium * jana.faes@ugent.be Keywords: steel fibers, fabric reinforced composite, meso scale modeling Abstract This paper studies the mechanical behavior of steel fiber fabric reinforced epoxy composite on meso scale. The fabric involved is a 4-harness satin weave of innovative steel fibers with a 30 μm diameter. Static tensile tests have been conducted on 4-layer laminates in both principal directions. Mechanical properties were determined based on strain gauge results and full field strain maps were monitored using the Digital Image Correlation technique. Microscopy was performed during the loading process on a polished edge of the coupons. In addition to the experimental study, a finite element unit cell model has been designed based on micro-CT scans of the fabric architecture. An elastic-plastic constitutive behavior was incorporated for both yarns and matrix, in order to fully capture the toughness of this novel material. Both experiments and simulations show that the ductility of the steel fibers could be exploited even more if the cracking of the non-loadbearing yarns could be delayed. 1. Introduction Improved technologies allow the production of steel fibers with a diameter of about 30 μm, which makes them suitably thin for use as polymer composite reinforcement. A competitive stiffness together with a high ductility that cannot be found among the traditional fiber materials makes these steel fibers very promising for applications in which a high toughness is demanded. This research focusses on the meso scale mechanical behavior of an epoxy composite with a 4-harness satin weave steel fiber reinforcement. First, results from static tensile experiments on 4-layer fabric laminates are presented. The in-plane mechanical properties were determined based on strain gauge results and damage initiation and evolution were observed microscopically on a polished edge of the coupons during the loading process. The Digital Image Correlation (DIC) technique was employed to map full field surface strains and to detect local strain concentrations. Next, the static tensile behavior of a Representative Volume Element (RVE) of the material structure was analyzed numerically using Abaqus finite element software. Geometry of the RVE was determined using micro-CT scans of the composite material and elastic-plastic constitutive models were proposed for both yarns and matrix.