Computational models for brittle fracture

Conference · Wed Dec 31 04:00:00 EST 1997

OSTI ID:567913

Jagota, A ^[1]; Bennison, S J ^[2]

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1. Indian Institute of Technology, Delhi (India)
2. E.I. DuPont de Nemours & Co., Inc., Wilmington, DE (United States)

Issues relating to the development of quantitative computational models for brittle fracture of disordered microstructures are discussed. We examine the use of spring-network (SN) and finite-element (FE) models where fracture is simulated by the removal or fragmentation of elements or element boundaries. Some basic questions regarding the validity of such models for fracture that have only recently been raised are considered. SN models are not always able to capture a state of uniform stress. The use of local element breaking rules based on critical stress or energy leads to Griffith scaling of fracture strength, provided a length scale is included in the breaking rule. However, the perfect strength of the model is then far too low; this leads us to propose that different failure rules be used for elements at a crack tip and those removed from it. Regular meshes that obviate this problem introduce some randomness in the scaling of fracture strength with crack length.

• OSTI ID: 567913
• Report Number(s): CONF-9505249--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
99 GENERAL AND MISCELLANEOUS
CRACK PROPAGATION
FINITE ELEMENT METHOD
FRACTURE PROPERTIES
MICROSTRUCTURE
RANDOMNESS