Fatigue behavior of maraging steel 300

The cyclic stress-strain curves, the low cycle and high cycle fatigue lives and the fatigue crack growth rates of annealed (1 h 820°C) and aged (3 h 480°C) maraging steel 300 were determined. Incremental step testing and stable hysteresis loop tip measurements were used to determine the cyclic σ-ε curves. Both annealed and aged maraging steels were found to cyclically soften at room temperature over a plastic strain range from 0.1 to 20 pct. The S-N curves were determined from 10 to 107 cycles to failure by plastic strain controlled low cycle fatigue tests performed in air and load controlled high cycle fatigue tests performed in dry argon. The test results compared very well with the theoretical lifetime predictions derived from Tomkins’ theory. Fatigue crack growth rates were measured in air and dry argon for the annealed and aged alloys. Crack growth rates of annealed maraging steel were found to be equal to those of aged maraging steel at rates between 10-7 and 10-5 in./cycle. A significant difference in crack growth rates in the two environments was found at low stress intensity factor ranges, indicating a high susceptibility to corrosion fatigue in the presence of water vapor. The mechanisms of cyclic softening in the two alloys are discussed in terms of dislocations rearrangement in the annealed alloy and dislocation-precipitate interactions in the aged alloy.

[1]  D. Wilson.  Reversible work hardening in alloys of cubic metals , 1965 .

[2]  B. Tomkins,et al.  Fatigue failure in high strength metals , 1971 .

[3]  RW Landgraf,et al.  The Resistance of Metals to Cyclic Deformation , 1970 .

[4]  B. Tomkins.  FATIGUE CRACK PROPAGATION: AN ANALYSIS. , 1968 .

[5]  J. Grosskreutz.  Development of Substructure in Polycrystalline Aluminum During Constant-Strain Fatigue , 1963 .

[6]  C. Bathias,et al.  Fatigue crack propagation in martensitic and austenitic steels , 1973 .

[7]  A. Plumtree,et al.  On the steady state cyclic deformation of iron , 1971 .

[8]  Lf Coffin,et al.  Manual on Low Cycle Fatigue Testing , 1969 .

[9]  J. Mcgrath,et al.  Interaction of dislocations and precipitates in quench-aged iron-carbon alloys subjected to cyclic stressing , 1967 .

[10]  S. S. Manson,et al.  Fatigue Behavior of Materials under Strain Cycling in Low and Intermediate Life Range , 1963 .

[11]  J. Pratt.  Dislocation substructure in strain-cycled copper as influenced by temperature , 1967 .

[12]  B. Cullity,et al.  Elements of X-ray diffraction , 1957 .

[13]  C. Feltner,et al.  Microplastic Strain Hysteresis Energy as a Criterion for Fatigue Fracture , 1961 .

[14]  A Abel,et al.  The cyclic strain behaviour of crystals of aluminum-4 wt.% copper-i. the bauschinger effect , 1966 .

[15]  J. Morrow.  Cyclic Plastic Strain Energy and Fatigue of Metals , 1965 .

[16]  Charles S. Barrett,et al.  The Structure of Metals , 1904, Nature.

[17]  C. Bauer,et al.  Solute atom-dislocation binding energy in dilute Cu-Ge alloys , 1964 .

[18]  R. W. Landgraf.  Cyclic Deformation and Fatigue Behavior of Hardened Steels , 1968 .

[19]  H. Uhlig,et al.  Corrosion fatigue of type 4140 high strength steel , 1972 .

[20]  J. Moteff,et al.  Characterization of the deformation substructure of AISI 316 stainless steel after high strain fatigue at elevated temperatures , 1972 .

[21]  C. Laird,et al.  Cyclic stress—strain response of two-phase alloys Part I. Microstructures containing particles penetrable by dislocations , 1974 .