Accession Number : ADA312441

Title :   Size and Deformation Limits to Maintain Constraint in K sub Ic and J sub c Testing of Bend Specimens.

Descriptive Note : Technical rept. 1 Jan-31 Dec 93,

Corporate Author : ILLINOIS UNIV AT URBANA DEPT OF CIVIL ENGINEERING

Personal Author(s) : Koppenhoefer, K. C. ; Dodds, R. H., Jr

PDF Url : ADA312441

Report Date : OCT 1995

Pagination or Media Count : 26

Abstract : The ASTM Standard Test Method for Plane-Strain Fracture Toughness of Metallic Materials (E399-90) restricts test specimen dimensions to insure the measurement of highly constrained fracture toughness values (K sub Ic). These requirements insure small-scale yielding (SSY) conditions at fracture, and thereby the validity of linear elastic fracture mechanics. Recently, Dodds and Anderson have proposed a less restrictive size requirement for cleavage fracture toughness measured in terms of the J-integral (Jc), as given by a,b,B greater than or equal 200 Jc/sigma sub 0. The size requirement proposed by Dodds and Anderson increases the applicability of fracture toughness experiments by expanding the range of conditions over which fracture toughness data meeting SSY conditions can be reliably measured. This investigation compares the proposed size requirement with that of ASTM Standard Test Method E399 and, by comparison with published experimental data for various alloys, provides validation of the new requirements.

Descriptors :   *METALS, *DEFORMATION, *ELASTIC PROPERTIES, *BENDING, *FRACTURE(MECHANICS), REQUIREMENTS, EXPERIMENTAL DATA, SIZES(DIMENSIONS), TEST METHODS, TOUGHNESS, STRAIN(MECHANICS), ALLOYS, LINEARITY, STANDARDIZATION, CLEAVAGE, J INTEGRALS.

Subject Categories : Mechanics
      Inorganic Chemistry
      Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE