Random-Fuzzy Model for the Ductile/Brittle Transition

LÜ Zhen-zhou; YUE Zhu-feng; FENG Yun-wen

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Article Navigation > Applied Mathematics and Mechanics > 2003 > 24(10): 1027-1034

LÜ Zhen-zhou, YUE Zhu-feng, FENG Yun-wen. Random-Fuzzy Model for the Ductile/Brittle Transition[J]. Applied Mathematics and Mechanics, 2003, 24(10): 1027-1034.

Citation:

LÜ Zhen-zhou, YUE Zhu-feng, FENG Yun-wen. Random-Fuzzy Model for the Ductile/Brittle Transition[J]. Applied Mathematics and Mechanics, 2003, 24(10): 1027-1034.

Citation:

LÜ Zhen-zhou, YUE Zhu-feng, FENG Yun-wen. Random-Fuzzy Model for the Ductile/Brittle Transition[J]. Applied Mathematics and Mechanics, 2003, 24(10): 1027-1034.

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Random-Fuzzy Model for the Ductile/Brittle Transition

1.
Department of Aircraft Engineering, Northwestern Polytechnical University, Xi'an 710072, P.R.China;
2.
Department of Engineering Mechanics, Northwestern Polytechnical University, Xi'an 710072, P.R.China

Received Date: 2000-03-09
Rev Recd Date: 2003-05-13
Publish Date: 2003-10-15

Abstract

Abstract

A large sample of experiments was carried out to study influence of stress triaxiality and temperature on the growth of micro voids and the ductile/brittle transition(DBT)behavior of 40Cr steel.A random-fuzzy model was put forward for the transition.It is assumed that the ductile fracture is controlled by the micro void mechanism,and the critical void growth ratio can be used as the criterion of ductile fracture.The brittle fracture is modeled by an embedded penny crack.A micro stress intensity and the fracture characteristic length of the brittle fracture was then presented and calculated. The DBT is completed by the two mechanisms,which exists in the fracture of all specimens simultaneously.The distributions of model parameters were measured experimentally.A random model and a random-fuzzy model for DBT were presented.The comparison between the calculated and experimental results shows that the random-fuzzy model can model the DBT satisfactorily.
- ductile/brittle transition,
- fracture criterion,
- randomness,
- fuzziness

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References(8)

References

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