Accession Number : ADA217752


Title :   Strength and Microstructure of Ceramics


Descriptive Note : Final technical rept. 1987-1989


Corporate Author : NATIONAL INST OF STANDARDS AND TECHNOLOGY GAITHERSBURG MD CERAMICS DIV


Personal Author(s) : Lawn, Brian R ; Alpert, C J ; Bennison, S J ; Chan, H M ; Cho, S-J ; Cook, R F ; Fairbanks, C J ; Harmer, M P ; Hockey, B J ; Marshall, D B


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a217752.pdf


Report Date : Nov 1989


Pagination or Media Count : 240


Abstract : Results of a study program on the toughness properties of monophase ceramics are summarized. In situ observations of crack propagation in alumina and other monophase ceramics show crack interface bridging to be the principal source of increasing toughness with crack size, i.e. R-curve behavior. Fracture mechanics models describing this behavior, in the particular context of strength, are developed. Results of strengths tests confirming the essential predictions of the theory are presented. Results of wear and fatigue tests are also described. The model has strong implications concerning the controlled processing of ceramics for optimum toughness and strength properties. Keywords; Strength mechanics; Fracture resistance; Brittleness; Heat treatment; Toughening; Mechanical properties.


Descriptors :   *CRACK PROPAGATION , *CERAMIC MATERIALS , *MICROSTRUCTURE , MECHANICAL PROPERTIES , OPTIMIZATION , SIZES(DIMENSIONS) , PREDICTIONS , INTERFACES , PROCESSING , RESISTANCE , CRACKS , THEORY , TOUGHNESS , STRENGTH(MECHANICS) , FRACTURE(MECHANICS) , HEAT TREATMENT , BRITTLENESS , ALUMINUM OXIDES , WEAR , CONTROL , FATIGUE TESTS(MECHANICS) , TEST AND EVALUATION , MATHEMATICAL MODELS


Subject Categories : Ceramics, Refractories and Glass
      Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE