Toughness, Strength, and R-Curve Behavior of Microcracking  Materials (Materials Research)
{'Code': '03070004', 'Directorate': {'Abbreviation': 'MPS', 'LongName': 'Direct For Mathematical & Physical Scien'}, 'Division': {'Abbreviation': 'DMR', 'LongName': 'Division Of Materials Research'}}
{'SignBlockName': 'John C. Hurt', 'PO_EMAI': None, 'PO_PHON': None}
This research is continuation of work (previous research                   under DMR-8305800) on understanding the toughness and stress-                   induced microcracking of ceramic materials.  The investigation                  emphasizes the following topics: 1) computer computation and                    modelling of the growth of cracks in ceramics which incorporates                the important physical materials parameters, 2) characterization                of ceramic-glass composites systems which demonstrate stress-                   induced microcracking using small angle neutron scattering, 3)                  study of the strength-toughness relationships for ceramics and                  ceramic-glass composites.                                                            In multiphase ceramic materials, microcracking is common,                  especially when there is a pronounced difference in the                         coefficient of thermal expansion between the several phases                     present in the material.  This phenomenon can be used to tailor                 the mechanical behavior of the material, by proper selection of                 the various phases, to allow elimination of the microcracks or                  introduction of the microcracks in the vicinity of regular cracks as            desired.  The presence of microcracks can often reduce the                      stress intensity at the tips of regular cracks, and thereby cause the           regular cracks to stop propagating.  This phenomenon causes                     the ceramic to be tougher in service, and less susceptible to                   catastropic failure under stress.  The present research is                      designed to increase understanding of the phenomenon, and allow                 design of tougher ceramics.
{'FirstName': 'Katherine', 'LastName': 'Faber', 'PI_MID_INIT': 'T', 'PI_SUFX_NAME': None, 'PI_FULL_NAME': 'Katherine T Faber', 'EmailAddress': 'ktfaber@caltech.edu', 'NSF_ID': '000119705', 'StartDate': '07/01/1987', 'EndDate': None, 'RoleCode': 'Principal Investigator'}
{'Name': 'Ohio State University Research Foundation -DO NOT USE', 'CityName': 'Columbus', 'ZipCode': '432101016', 'PhoneNumber': '6146888734', 'StreetAddress': '1960 KENNY RD', 'StreetAddress2': None, 'CountryName': 'United States', 'StateName': 'Ohio', 'StateCode': 'OH', 'CONGRESSDISTRICT': '03', 'CONGRESS_DISTRICT_ORG': 'OH03', 'ORG_UEI_NUM': 'QR7NH79713E5', 'ORG_LGL_BUS_NAME': None, 'ORG_PRNT_UEI_NUM': None}
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{'Code': '1772', 'Text': 'CERAMICS & ELECTRONIC MATERIAL'}
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