ISSN: 0090-3973
Page Count: 8

The Use of an Alternative Method for Fracture Toughness Evaluation on Different Materials
Guardiola, M
Engineer, REPSOL YPF, Argentina

Bernal, C
Research Doctor, Institute of Materials Science and Technology (INTEMA),

Martínez, R
Research Doctor, Institute of Materials Science and Technology (INTEMA),

Cassanelli, A
Research Doctor, National University of Mar del Plata,

(Received 9 June 2003; accepted 17 March 2004)

Abstract

Through this paper an alternative procedure to obtain fracture toughness parameters on blunt-notched samples rather than on standard sharp-notched samples has been applied to several materials which display different fracture behavior. An aluminum alloy, an austempered ductile iron (ADI), and two different polymeric materials, polyamide 6 and poly(methyl methacrylate) (PMMA), were tested. The use of the alternative methodology allows simplification and cost reduction in fracture toughness evaluation. For the aluminum alloy, the fracture parameter obtained by this method was 16 % lower than that determined using ASTM standard methodology with data scatter similar to that reported in literature. For the ADI, fracture toughness values from blunt-notched samples were close to those obtained using standard test samples, showing low sensitivity to the changes in the crack tip diameter. For polyamide 6, the alternative methodology led to a toughness value within the same range of the values obtained from the traditional technique. In the case of the PMMA, the K^Ic values obtained from both methods showed good agreement.

Keywords:
fracture toughness, stress intensity factor, J-integral, blunt-notched samples, toughness assessment

Paper ID: JTE11977
DOI: 10.1520/JTE11977
ASTM International is a member of CrossRef.