Accession Number : ADD018607

Title :   Test Specimen Design Incorporating Multiple Fracture Sites and Multiple Strain State Material Fractures

Descriptive Note : Patent Application, Filed 28 Apr 97,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Matic, Peter ; Everett, Richard ; Deqiorqi, Virginia ; Geltmacher, Andrew

PDF Url : ADD018607

Report Date : 28 Apr 1997

Pagination or Media Count : 24

Abstract : A material test specimen design is taught for the determination of critical strain and stress states for multiaxial fracture. The objective of the specimen is to increase the amount of data obtained per specimen while retaining simplicity in testing procedure by using standard tension testing machines to generate the primary deformation of the specimen. The specimen, in conjunction with analytical or computational simulation, uses nonuniform deformation fields produced by secondary and tertiary strain concentrations to generate and track these multiaxial strain states to fracture. Typically, the primary deformation is uniaxial tension of a panel, the secondary strain concentration is a circular hole in the panel and the tertiary strain concentrations are areas of reduced thickness within the deformation field of the circular hole. Multiaxial strain ratios from -0.50 to -0.10 and control over fracture initiation sites may be generated by a test specimen design of the type taught by this invention.

Descriptors :   *PATENT APPLICATIONS, *FRACTURE(MECHANICS), *STRUCTURAL INTEGRITY, METALS, STRESS ANALYSIS, EXPERIMENTAL DESIGN, DEFORMATION, TEST EQUIPMENT, STRAIN(MECHANICS), TENSION

Subject Categories : Test Facilities, Equipment and Methods
      Mechanics
      Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE