Issue 41

S. Doddamani et alii, Frattura ed Integrità Strutturale, 41 (2017) 484-490; DOI: 10.3221/IGF-ESIS.41.60 484 Fracture toughness investigations of Al6061-Graphite particulate composite using compact specimens Saleemsab Doddamani Department of Mechanical Engineering, Jain Polytechnic, Karnataka, India, saleemsabdoddamani@gmail.com , http://orcid.org/0000-0002-8498-1488 Mohamed Kaleemulla Department of Studies in Mechanical Engineering, University B.D.T. College of Engineering, Karnataka, India. A BSTRACT . The objective of this research work is to study the fracture behavior of Al6061 with graphite particulate composite produced by the stir casting technique. For the study different composition of the particulate metal matrix composite used is Al6061 with 3, 6, 9, & 12% of graphite particles. Compact Tension (CT) specimens were utilized to determine fracture toughness for different compositions of Al6061-graphite particulate metal matrix composite. Specimens with different composition will be prepared for different crack length to width (a/w) ratios according to the ASTM E-399 standard testing procedure. The maximum fracture toughness was found for Al6061-9%Gr for a/w =0.45 and the value is 16.74 MPa √m. K EYWORDS . Fracture toughness; Al6061-Graphite Composites; Compact Tension specimens Citation: Doddamani, S., Kaleemulla, M., Fracture toughness investigations of Al6061- Graphite particulate composite using compact specimens, Frattura ed Integrità Strutturale, 41 (2017) 484-490. Received: 07.02.2017 Accepted: 28.05.2017 Published: 01.07.2017 Copyright: © 2017 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. I NTRODUCTION ll structural materials do not have theoretically calculated strength because of imperfections like inclusions, flaws, cracks and manufacturing defects, etc. The fracture based design approach is better compared to the conventional design. In conventional design, limiting strength approach is adopted. In actual service, the components will fail before reaching its limiting strength. “The resistance to fracture of a material is known as fracture toughness.” Generally it depends upon the material composition, environment, temperature, loading rate, microstructure and geometrical parameters of the component, etc. Fracture toughness is a material property which expresses the capacity of a material having a crack to oppose fracture. For many design applications, fracture toughness is the most important property of a material. Linear elastic fracture toughness (LEFM) of a material is calculated from the stress intensity factor (SIF) at which a thin crack in the material begins to grow catastrophically. Fracture toughness is represented by K Ic . Its unit in SI is MPa  m. In K Ic , subscript Ic represents first mode crack opening under tensile loading at right angles to the crack. Fracture toughness could be a A