Creep Failure Analysis of Bars Sustaining Constant Tensile Loads

Springer Science and Business Media LLC - Tập 4 - Trang 57-79 - 2000
Y. Germain1,2, A. Molinari1,2
1Elf Atochem, Cerdato, Serquigny, France
2Laboratoire de Physique et Mécanique des Matériaux, ISGMP-CNRS, Université de Metz, Metz Cedex, France

Tóm tắt

Life time and failure modes are predicted for metallic barssustaining tensile creep. Experimental results show that a ductile or a`brittle' mode of fracture occurs depending respectively on whether thenominal applied stress is large or small. The analysis is based on amodeling of void nucleation and growth in which damage evolution iscontrolled by two mechanisms of plastic flow in the matrix material.Fracture is supposed to occur when the porosity attains a critical valuewhich depends on the mode of fracture considered. Experimental resultsare explained and described in terms of the proposed model.

Tài liệu tham khảo

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