A Study of Ductile Crack Corrections for Elastic-Plastic Fracture Toughness Tests

Published

October 14, 2023

Author(s)

Enrico Lucon

Abstract

This paper critically examines existing ductile crack growth (DCG) corrections for J integral values calculated with the multi-specimen and elastic compliance approaches, as well as two novel/alternative DCG corrections. The benchmark is represented by the incremental DCG correction prescribed by ASTM E1820-21 for Elastic Compliance tests. Considering calculations performed at both end-of-test and intermediate conditions, most of the existing and proposed approaches tend to under-correct J values, by an amount proportional to the percentage of cracked initial ligament. For one of the proposed novel approaches (Pseudo-Resistance Curve Procedure), a tendency to overcorrection was observed. Nevertheless, when values of critical toughness (JQ, JIc) and ductile crack resistance (expressed by the tearing modulus, TM) are considered, differences are smaller than the typical uncertainties associated with elastic-plastic fracture toughness test results. Therefore, it does not appear necessary to modify the DCG corrections currently prescribed in the two most widely used fracture toughness test standards (ASTM E1820 and ISO 12135).

Citation

Theoretical and Applied Fracture Mechanics

Volume

128

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.tafmec.2023.104139

Local Download

Keywords

ASTM E1820, critical toughness, ductile crack growth (DCG) correction, crack resistance, Elastic Compliance tests, incremental crack growth correction, ISO 12135, multi-specimen procedure, tearing modulus.

Citation

Lucon, E. (2023), A Study of Ductile Crack Corrections for Elastic-Plastic Fracture Toughness Tests, Theoretical and Applied Fracture Mechanics, [online], https://doi.org/10.1016/j.tafmec.2023.104139, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=935316 (Accessed April 27, 2024)