Prediction of crack paths based upon detailed microstructure characterization in a neair-γ TiAl Alloy

B. C. Ng, T. R. Bieler, M. A. Crimp, D. E. Mason

Research output: Chapter in Book/Report/Conference proceedingConference contribution

  • 4 Citations

Abstract

Fracture in a duplex γ -TiAl alloy with equiaxed grains has been studied. The crack path in a notched Mode I crack growth specimen was analyzed using a combination of orientation imaging microscopy and selected angle channeling patterns (to obtain the true c-axis orientation in each grain). A phenomenological fracture propagation parameter incorporating the contributions from deformation twinning and ordinary dislocation systems has been developed that is capable of identifying boundaries that are likely to nucleate microcracks. This fracture propagation parameter was then used to analyze the existing crack path to identify why sharp turns in the crack path occurred. With this understanding, grain boundaries in the microstructure ahead of the crack tip were analyzed to predict the expected fracture path, and to compare it to the actual crack path. Based upon this parameter, criteria for crystal orientations and misorientations for high toughness microstructures are proposed.

LanguageEnglish (US)
Title of host publicationMaterials Damage Prognosis - Proceedings of a Symposium of the Materials Science and Technology 2004 Conference
EditorsJ.M. Larsen, L. Christodoulou, J.R. Calcaterra, M.L. Dent, M.M. Derriso, W.J. Hardman, J. Wayne Jones, S.M. Rusa
Pages307-314
Number of pages8
StatePublished - 2005
EventMaterials Damage Prognosis - a Symposium of the Materials Science and Technology 2004 Conference - New Orleans, LA, United States
Duration: Sep 26 2004Sep 30 2004

Other

OtherMaterials Damage Prognosis - a Symposium of the Materials Science and Technology 2004 Conference
CountryUnited States
CityNew Orleans, LA
Period9/26/049/30/04

Profile

Cracks
Microstructure
Crack propagation
Twinning
Microcracks
Dislocations (crystals)
Crack tips
Crystal orientation
Toughness
Microscopic examination
Grain boundaries
Imaging techniques

Keywords

  • Crack Propagation
  • Fracture
  • Microcrack
  • TiAl
  • Twinning

ASJC Scopus subject areas

  • Engineering(all)

Cite this

Ng, B. C., Bieler, T. R., Crimp, M. A., & Mason, D. E. (2005). Prediction of crack paths based upon detailed microstructure characterization in a neair-γ TiAl Alloy. In J. M. Larsen, L. Christodoulou, J. R. Calcaterra, M. L. Dent, M. M. Derriso, W. J. Hardman, J. Wayne Jones, ... S. M. Rusa (Eds.), Materials Damage Prognosis - Proceedings of a Symposium of the Materials Science and Technology 2004 Conference (pp. 307-314)

Prediction of crack paths based upon detailed microstructure characterization in a neair-γ TiAl Alloy. / Ng, B. C.; Bieler, T. R.; Crimp, M. A.; Mason, D. E.

Materials Damage Prognosis - Proceedings of a Symposium of the Materials Science and Technology 2004 Conference. ed. / J.M. Larsen; L. Christodoulou; J.R. Calcaterra; M.L. Dent; M.M. Derriso; W.J. Hardman; J. Wayne Jones; S.M. Rusa. 2005. p. 307-314.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Ng, BC, Bieler, TR, Crimp, MA & Mason, DE 2005, Prediction of crack paths based upon detailed microstructure characterization in a neair-γ TiAl Alloy. in JM Larsen, L Christodoulou, JR Calcaterra, ML Dent, MM Derriso, WJ Hardman, J Wayne Jones & SM Rusa (eds), Materials Damage Prognosis - Proceedings of a Symposium of the Materials Science and Technology 2004 Conference. pp. 307-314, Materials Damage Prognosis - a Symposium of the Materials Science and Technology 2004 Conference, New Orleans, LA, United States, 9/26/04.
Ng BC, Bieler TR, Crimp MA, Mason DE. Prediction of crack paths based upon detailed microstructure characterization in a neair-γ TiAl Alloy. In Larsen JM, Christodoulou L, Calcaterra JR, Dent ML, Derriso MM, Hardman WJ, Wayne Jones J, Rusa SM, editors, Materials Damage Prognosis - Proceedings of a Symposium of the Materials Science and Technology 2004 Conference. 2005. p. 307-314.
Ng, B. C. ; Bieler, T. R. ; Crimp, M. A. ; Mason, D. E./ Prediction of crack paths based upon detailed microstructure characterization in a neair-γ TiAl Alloy. Materials Damage Prognosis - Proceedings of a Symposium of the Materials Science and Technology 2004 Conference. editor / J.M. Larsen ; L. Christodoulou ; J.R. Calcaterra ; M.L. Dent ; M.M. Derriso ; W.J. Hardman ; J. Wayne Jones ; S.M. Rusa. 2005. pp. 307-314
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