Prediction of corrosion fatigue crack propagation life for welded joints under cathodic potentials

• Autorzy: Jakubowski M.
• Języki publikacji: EN

Abstrakty

EN

Enhancement of corrosion fatigue crack growth rates by cathodic protection is observedbelow the optimum applied potential of the protection. An empirical formula for theeffect of the protective potential below -0.8 V (Ag/AgCl2) on the crack growth rates forsome classes of shipbuilding steels tested in salt water has been derived for medium andhigh value ranges of the stress intensity factor. For the lower value range the formulareflects a relatively steep decrease of the crack growth rates (against the same values inair) along with decreasing the stress intensity factor range. A simple formula for thecorrosion fatigue crack propagation life under cathodic potential has been derived for fillet weldedjoints in bending by integrating the corrosion fatigue kinetic characteristics. The new formula for thestress intensity factor range has been used for the bent joint. The predicted "S-Np" curves have beencompared with experimental data, taken from literature, for two different values of both applied potentialand the plate thickness. The predicted curves correspond approximately to lower bounds of the testresults. The presented procedure can be applied to joints of higher strength steels (of the yield strength σY= 315 and 355 MPa) fatigued at any applied cathodic potential below -0.8 V under sea loadingof (0.05÷0.2 Hz) frequency at (0÷0.2) stress ratios

• Wydawca: -
• Czasopismo: Polish Maritime Research
• Rocznik: 2005
• Tom: 12
• Numer: 2
• Opis fizyczny: p.17-20,fig.,ref.

Twórcy

autor

Jakubowski M.

• Faculty of Ocean Engineering and Ship Technology, Gdansk University of Technology, Narutowicza 11/12, 80-952 Gdansk, Poland

Bibliografia

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