Growth modes of cracks in creeping type 304 stainless steel

doi:10.1016/0167-6636(91)90036-Y

Mechanics of Materials

Volume 11, Issue 1, March 1991, Pages 1-17

https://doi.org/10.1016/0167-6636(91)90036-Y Get rights and content

Abstract

The modes of initial growth of cracks in creeping Type 304 stainless steel were studied in the 600–775°C range in plane strain and three different test geometries consisting of center cracked panels, double edge notched bars, and compact tension specimens in both annealed material and in some material with 5% initial cold work. In all cases it was found that in samples with pre-fatigue sharpened cracks the initial growth was branched and on planes at 50° with the median plane of the crack. In other cases of samples with blunt cracks having machined radii of curvature, initial growth was found to remain in the median plane of the crack. In further growth, however, it was noted that while the direction of the branched cracks became later parallel to the median crack plane, the initially planar cracks showed later evidence of branching. This meandering behavior of cracks is a result of the different nature of crack tip strain concentration for initially sharp and initially blunt cracks.

While data were limited, a dependence of the average crack speed on a power function of the $C∗$ parameter was found for all cases in which crack growth was intergranular.

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¹: Now at Texas Instruments Company in Dallas, Texas, U.S.A.

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Growth modes of cracks in creeping type 304 stainless steel

Abstract

Acta Metall.

Int. J. Solids Struct.

Acta. Metall.

Acta. Metall.

Mater. Sci. Eng.

Acta Metall.

Acta Metall.

Mech. Mater.

EPRI Topical Report NP-1931

J. Eng. Mater. Technol.

J. Mech. Phys. Solids

Int. J. Fracture

Metall. Trans.

Eng. Fract. Mech.

Creep crack growth in ductile alloys

Creep crack extension by grain boundary cavitation

Isochonous stress-strain curves for austenitic stainless steels

Effect of notch geometry on rupture strength at elevated temperatures

Creep of Nimonic 80A in torsion and tension

Metal Sci.

The effect of varying degrees of cold work on the stress-rupture properties of Type 304 stainless steel

J. Eng. Mater. Technol.

High temperature crack growth in a 212Cr-1Mo weld metal - effects of tempering, prestrain and grain refinement

Mater. Sci. Eng.

The role of continuum damage in creep crack growth

Phil. Trans. R. Soc.

Development of continuum damage in the creep rupture of notched bars

Phil. Trans. R. Soc.

Transient crack growth under creep conditions

J. Mech. Phys. Solids.

High temperature crack growth in a $212 Cr-1Mo$ weld metal - effects of tempering, prestrain and grain refinement