For materials which fail by void coalescence and growth, and possibly for solids failing by other mechanisms, it is commonly held that increasing tensile hydrostatic stress states at fracture produce lower strains to fracture. In tests on sheet material there is a marked change in strain ratio before fracture if plane-strain necking occurs. Then it may be shown that at the instant of fracture the current hydrostatic stress is most tensile for the greatest strains to fracture. These contrary observations may be explained by means of, path-dependent damage functions which involve not only the hydrostatic stress and effective strain but also the current strain ratio.
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References
1.
HANCOCKJ. W. and McKENZIEA. C.: J. Mech. Phys. Solids, 1976, 24, 147.
2.
GOODSs. H. and BROWNL. M.: Acta Metall., 1979, 27, 1.
3.
BRIDGMANP. W.: ‘Studies in large plastic flow and fracture’; 1952, New York, McGraw-Hill.
4.
McCLINTOCKF. A.: J. Appl. Mech., 1968, 35, 363.
5.
RICEJ. R. and TRACEYD. M.: ibid., 1969, 17, 201.
6.
KUDOH. and AOIR.: J. Jpn Soc. Tech. Plasticity, 1967, 8, 17.
7.
KUHNH. A. and DIETERG. E.: ‘Fracture 1977’, Vol. 1, ICF4, Waterloo, Ont., Canada.
8.
ATKINSA. G.: unpublished work, 1979.
9.
KOBAYASHIS.: J. Eng. Ind., 1970, 928, 391.
10.
THOMASONP. F.: Int. J. Mech. Sci., 1969, 11, 187.
11.
EMBURYJ. D. and LeROYG. H.: ‘Fracture 1977’, Vol. 1, ICF4, Waterloo, Ont., Canada; (see also McMaster University, Faculty of Engineering Metalworking and Design Group Report No. 115, 1977).
12.
NORRISD. M., REAUGHJ. E., MORANB., and QUISIONESD. F.: J. Eng. Mater. Technol., 1978, 100, 279.
13.
ATKINSA. G.: to be published.
14.
TOMKINSB. and ATKINSA. G.: Int. J. Mech. Sci.: forthcoming.
15.
RICEJ. R. and SORENSENE. P.: J. Mech. Phys. Solids, 1978, 26, 163.
