ISSN: 1945-7553
CODEN: JTEVAB
Page Count: 6

Determination of K_c and Residual Strength Values for Sheet Materials

Abril, ER
Professor Emeritus, Universidad Nacional de Córdoba,

(Received 10 February 1986; accepted 24 April 1987)

Abstract

Obtaining values of K_c for sheets of high-toughness materials presents difficulties related to the plastic behavior of such materials. These difficulties are also encountered in the determination of the residual strength of cracked sheets.

In this paper, an attempt is made at avoiding such difficulties by means of an empirical interpretation of K_c and the assumption of some hypotheses, experimentally verified, about the behavior of centrally cracked sheets under tension.

An empirical expression for the gross-area stress at maximum load as a function of the initial crack length is obtained and, from this expression, K_c values are calculated. For this purpose, K_c is assumed to be proportional to the maximum of the product of such stress times the square root of the corresponding initial crack length, when infinitely wide sheets are considered. A procedure is established to pass from empirical values obtained with sheets of any width to the corresponding values for a sheet of infinite width.

Keywords:
fracture mechanics, thin sheet materials, fracture toughness, residual strength, fracture testing, fracture parameters

Paper ID: JTE11050J
DOI: 10.1520/JTE11050J
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