Investigation and modeling of the kinetics of the development of corrosion-fatigue cracks

1978 ◽  
Vol 13 (3) ◽  
pp. 235-239
Author(s):  
N. N. Vasserman ◽  
V. A. Merkushev ◽  
M. S. Nemanov
Keyword(s):  
Corrosion Fatigue ◽  
Fatigue Cracks ◽  
Kinetics Of

scholarly journals Reliability Estimation of Transport Means Elements Under the Action of Cyclic Loads and Corrosive Environment

2018 ◽  
Vol 15 (4) ◽  
pp. 5793-5802
Author(s):  
P. V. Popovych ◽  
Volodymyr Dzyura ◽  
O. S. Shevchuk
Keyword(s):  
Fracture Mechanics ◽  
Corrosion Fatigue ◽  
Residual Life ◽  
Fatigue Cracks ◽  
Reliability Estimation ◽  
Analytical Models ◽  
Cyclic Loads ◽  
Corrosive Environment ◽  
17G1s Steel ◽  
Kinetics Of

The approach for determining the residual life of the vehicles’ thin-walled metal elements with cracks under the action of cyclic loads and corrosive environment is developed based on the first law of thermodynamics and the fracture mechanics principles. Based on the results of the mathematical description of electrochemical reactions and separate data of fracture mechanics, the equation describing the kinetics of the corrosion-fatigue cracks propagation is deduced. This equation and the initial and final conditions are a mathematical model for determining the residual life of structural elements. The correctness of the developed analytical models is confirmed by the experimental data known in the literature. The performance of this model is demonstrated on the example of determining the residual life of a plate made of 17G1S steel. The plate was diluted by a crack in a 3% NaCl solution and subjected to cyclic loading. An increase in the initial size of corrosion-fatigue cracks is significant to reduce the period of their subcritical growth.

Lifetime Enhancement of Propulsion Shafts Against Corrosion-Fatigue by Laser Peening

2018 ◽  
Author(s):  
Lloyd A. Hackel ◽  
Jon E. Rankin
Keyword(s):  
Corrosion Fatigue ◽  
Fatigue Testing ◽  
Salt Water ◽  
Fatigue Cracks ◽  
Water Immersion ◽  
High Energy ◽  
General Corrosion ◽  
Laser Peening ◽  
Corrosion Pits ◽  
Deep Pits

This paper reports substantially enhanced fatigue and corrosion-fatigue lifetimes of propulsion shaft materials, 23284A steel and 23284A steel with In625 weld overlay cladding, as a result of shot or laser peening. Glass reinforced plastic (GRP) coatings and Inconel claddings are used to protect shafts against general corrosion and corrosion pitting. However salt water leakage penetrating under a GRP can actually enhance pitting leading to crack initiation and growth. Fatigue coupons, untreated and with shot or laser peening were tested, including with simultaneous salt water immersion. Controlled corrosion of the surfaces was simulated with electric discharge machining (EDM) of deep pits enabling evaluation of fatigue and corrosion-fatigue lifetimes. Results specifically show high energy laser peening (HELP) to be a superior solution, improving corrosion-fatigue resistance of shaft and cladding metal, reducing the potential for corrosion pits to initiate fatigue cracks and dramatically slowing crack growth rates. At a heavy loading of 110% of the 23284A steel yield stress and with 0.020 inch deep pits, laser peening increased fatigue life of the steel by 1370% and by 350% in the corrosion-fatigue testing.

Effect of Organic Corrosion Inhibitors on Corrosion Fatigue

CORROSION ◽  
1967 ◽  
Vol 23 (3) ◽  
pp. 65-71 ◽  
Author(s):  
PARVIZ MEHDIZADEH ◽  
R. L. McGLASSON ◽  
J. E. LANDERS
Keyword(s):  
Corrosion Fatigue ◽  
Diesel Fuel ◽  
Corrosion Inhibitors ◽  
Fatigue Cracks ◽  
Material Surface ◽  
Significant Protection ◽  
Inhibitor Concentration ◽  
Degree Of Protection ◽  
Organic Inhibitors ◽  
Organic Corrosion Inhibitors

Abstract The effect of organic inhibitors on corrosion fatigue performance of steel in a mixture of brine containing H2S-CO2 and diesel fuel is reported. The inhibitor concentration required to give significant protection to steel under corrosion fatigue conditions is much higher than that for corrosion control. This is due to the fact that corrosion fatigue cracks initiated at incompletely protected spots on the material surface influence fatigue failure regardless of the degree of protection achieved on neighboring areas. Effects of fatigue stress and concentration of corrosion inhibitors were investigated. Results were analyzed in terms of the proposed mechanism for corrosion inhibition in these environments.

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