Accession Number : AD0784435

Title :   Reduction of Errors in Ceramic Bend Tests.

Descriptive Note : Technical rept.,


Personal Author(s) : Hoagland,R. G. ; Marschall,C. W. ; Duckworth,W. H.

Report Date : JUL 1974

Pagination or Media Count : 27

Abstract : Mechanical tests of most ceramics are subject to stringent requirements, more so than tests of materials which possess some ability to undergo plastic deformation. In this paper, sources of stress concentrations and spurious displacements which may be imposed during four-point bend tests of ceramic materials are identified and discussed. Particular areas of concern involve unequal moments at the loading points, twisting due to skewness of the contact lines, wedging stresses at point contacts, and counter moments produced by friction at the loading point-specimen interface. A bend fixture incorporating design features to significantly reduce these effects is described and results of measurements of the surface stresses in calibration specimens under load in the fixture are presented. (Author)

Descriptors :   *Ceramic materials, Bending, Test methods, Errors, Reduction

Subject Categories : Ceramics, Refractories and Glass

Distribution Statement : APPROVED FOR PUBLIC RELEASE