Conference Dates

May 29-June 3, 2016


It is well recognized that environment has significant effects on the failure of cyclically loaded members/structures Existing experimental data indicates that fatigue life is much shorter in corrosive environment that in more inert environment such as a dry air or vacuum. This paper presents a method and strategy to predict/estimate life under corrosion-fatigue. A corrosion fatigue factor kcorr is defined as the ratio of the fully-reversed stress amplitude in air, (a)air, over that in corrosive environment, (a)corr, for a given fatigue life in terms of a number of cycles to failure, Nf, i.e. kcorr = (a)air/(a)corr at the same Nf. The corrosion fatigue factor resembles the widely used fatigue notch factor kf. The proposed strategy requires the S-N curve in air and the corresponding kcorr factor. Experimental data for three materials, namely 7075-T651, 6161-T561 and 4140 steel tested in laboratory air and 3.5% of NaCl solution were used to illustrate and validate the proposed method. A fairly good agreement is demonstrated in terms of the correlation among air and corrosion-fatigue data.

Included in

Engineering Commons