Equibiaxial Low-Cycle Fatigue Properties of Typical Pressure-Vessel Steels

Large-size circular-plate specimens made of typical pressure-vessel materials were tested to determine their low-cycle fatigue strength. The test consisted of two distinct phases; i.e., development of an appropriate testing apparatus and the fatigue testing of the plate specimens. A unique apparatus was developed to test simply supported, circular plate-type specimens. Through a hydraulic system, a uniform pressure was applied to the specimen that resulted in a state of equibiaxial strain at the center of the plate. Tests were conducted to evaluate the pressure-deflection characteristics for various specimen strain levels. Biaxial fatigue data with a strain ratio (circumferential to radial) of 1:1 were generated for three pressure-vessel materials (A-201, A-302, T-1) for a completely reversed strain cycle. Initial cracking was used as a criterion of failure. Cracks were determined by monitoring electrical-resistance strain gages mounted on the specimen.

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In-Reactor Studies of Low-Cycle Fatigue Properties of a Nuclear Pressure Vessel Steel

Flow and Fracture of Metals and Alloys in Nuclear Environments ◽

10.1520/stp43539s ◽

2009 ◽

pp. 350-350-14 ◽

Cited By ~ 1

Author(s):

J. R. Hawthorne ◽

L. E. Steele

Keyword(s):

Pressure Vessel ◽

Low Cycle Fatigue ◽

Fatigue Properties ◽

Pressure Vessel Steel ◽

Cycle Fatigue ◽

Vessel Steel

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The Influence of Heat Treatment on Low Cycle Fatigue Properties of Selectively Laser Melted 316L Steel

Materials ◽

10.3390/ma13245737 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5737

Author(s):

Janusz Kluczyński ◽

Lucjan Śnieżek ◽

Krzysztof Grzelak ◽

Janusz Torzewski ◽

Ireneusz Szachogłuchowicz ◽

...

Keyword(s):

Heat Treatment ◽

Fatigue Testing ◽

Low Cycle Fatigue ◽

Negative Influence ◽

Material Behavior ◽

Fatigue Properties ◽

Cycle Fatigue ◽

316L Steel ◽

Material Fracture ◽

Precipitation Heat

The paper is a project continuation of the examination of the additive-manufactured 316L steel obtained using different process parameters and subjected to different types of heat treatment. This work contains a significant part of the research results connected with material analysis after low-cycle fatigue testing, including fatigue calculations for plastic metals based on the Morrow equation and fractures analysis. The main aim of this research was to point out the main differences in material fracture directly after the process and analyze how heat treatment affects material behavior during low-cycle fatigue testing. The mentioned tests were run under conditions of constant total strain amplitudes equal to 0.30%, 0.35%, 0.40%, 0.45%, and 0.50%. The conducted research showed different material behaviors after heat treatment (more similar to conventionally made material) and a negative influence of precipitation heat treatment of more porous additive manufactured materials during low-cycle fatigue testing.

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Damage Assessment on Low Cycle Fatigue Properties of Cyclic Pre-Strained Austenitic Stainless Steel

ASME 2011 Pressure Vessels and Piping Conference: Volume 1 ◽

10.1115/pvp2011-57832 ◽

2011 ◽

Cited By ~ 4

Author(s):

Nao Fujimura ◽

Hiroyuki Oguma ◽

Takashi Nakamura

Keyword(s):

Surface Roughness ◽

Stainless Steel ◽

Austenitic Stainless Steel ◽

Fatigue Damage ◽

Low Cycle Fatigue ◽

Strain Ratio ◽

Fatigue Properties ◽

Cycle Fatigue ◽

Damage Law ◽

Number Of Cycles

The effects of cyclic pre-strain on low cycle fatigue properties of austenitic stainless steel were investigated, and the fatigue damage was assessed based on several parameters such as the full width at half maximum (FWHM) of diffracted X-ray profile and surface roughness of specimens. The strain-controlled tests were conducted under strain ratio Rε = −1 and various constant total strain ranges. Also the change in remnant fatigue lives were investigated when the cyclic pre-strain were applied to the specimens under the different number of cycles which were determined with reference to the usage factor UFpre ranged from 0.2 to 0.8. As a result, the remnant fatigue life of the pre-strained samples became shorter than that of the sample without pre-strain as the UFpre increased. The relationship between the pre-strain damage expressed in UFpre and the remnant fatigue damage in UFpost was roughly described by the cumulative linear damage law: UFpre + UFpost = 1. Namely, the cyclic pre-strain affected the remnant fatigue lives. In order to evaluate the effects of cyclic pre-strain on fatigue lives more precisely, the damage in the cyclic pre-straining processes was estimated by using FWHM and surface roughness. The FWHM of the specimens with pre-strain once decreased with increase in UFpre, and then increased after showing a minimum value. The surface roughness of specimens increased linearly with an increase of the number of pre-straining cycles. These results suggested that the damage due to pre-strain can be assessed by means of FWHM and surface roughness of specimens.

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Fracture Modes and Low Cycle Biaxial Fatigue Life at Elevated Temperature

Journal of Engineering Materials and Technology ◽

10.1115/1.3225970 ◽

1987 ◽

Vol 109 (3) ◽

pp. 236-243 ◽

Cited By ~ 33

Author(s):

M. Sakane ◽

M. Ohnami ◽

M. Sawada

Keyword(s):

Low Cycle Fatigue ◽

Surface Oxidation ◽

Strain Ratio ◽

Growth Direction ◽

Principal Strain ◽

304 Stainless Steel ◽

Cycle Fatigue ◽

Biaxial Fatigue ◽

Crack Growth Direction ◽

Typical Strain

This paper describes the crack growth direction in biaxial low cycle fatigue under combined axial and torsional stresses in hollow cylindrical specimens of type 304 stainless steel at 923 K in air. Three types of crack are identified, namely macrocrack greater than 1 mm in length, subcracks between 0.1 mm and 1.0 mm in length, and microcracks less than 0.1 mm in length. The macrocrack direction as well as that of the subcrack depends on the principal strain ratio but the microcrack is mode I for all the principal strain ranges tested. The connection of the three types of crack is discussed in relation to the surface oxidation. Typical strain stress and criteria for the biaxial low cycle fatigue failure are applied to the experimental data and their applicability is discussed.

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The Effect of Hydrostatic Pressure Environment on the Low Cycle Fatigue Properties of a Maraging Steel

Journal of Engineering Materials and Technology ◽

10.1115/1.3443143 ◽

1973 ◽

Vol 95 (3) ◽

pp. 157-160 ◽

Cited By ~ 1

Author(s):

G. Lunsford ◽

A. W. Pense ◽

P. S. Venkatesan ◽

M. J. McIntosh

Keyword(s):

High Pressure ◽

Maraging Steel ◽

Fatigue Testing ◽

Low Cycle Fatigue ◽

Testing Machine ◽

Fluid Pressure ◽

Fatigue Properties ◽

Uniaxial Tensile ◽

Cycle Fatigue ◽

Effect Of Hydrostatic Pressure

To investigate the low cycle fatigue properties of an 18 percent nickel maraging steel, a high pressure fatigue testing machine including the high pressure chamber and associated hydraulic controls was designed and developed to apply simultaneously to the specimen (1) constant fluid pressure up to 100,000 psi, (2) mean uniaxial tensile or compressive stress, and (3) alternating push-pull load at a selected rate. Using this machine, notched and unnotched specimens were tested. Results indicated a definite increase in fatigue life of the material in the high pressure environment.

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Review of Margins Needed to Develop Fatigue Design Curves From Laboratory Test Data

Pressure Vessel and Piping Codes and Standards ◽

10.1115/pvp2003-1781 ◽

2003 ◽

Author(s):

W. A. Van Der Sluys

Keyword(s):

Fatigue Testing ◽

Low Cycle Fatigue ◽

Light Water Reactor ◽

Fatigue Properties ◽

Low Alloy Steels ◽

Test Results ◽

Cycle Fatigue ◽

Fatigue Design ◽

Current Design ◽

Alloy Steels

The PVRC has just completed a review of the effect of LWR (Light Water Reactor) coolant environment on the low cycle fatigue properties of carbon and low alloy steels. The PVRC has made recommendations to the ASME on changes to the boiler and pressure vessel codes to account for the environmental effects. In developing the recommendations, the margins used to produce the design curves from fatigue test results of laboratory specimens, were studied. This paper describes the margins used by the ASME in the development of the current design curves and discusses what margins should be applied when the laboratory fatigue testing includes tests in simulated LWR coolant environments.

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