Quantitative fractography of 2205 duplex stainless steel after a sulfide stress cracking test

This paper presents the results of SSC (Sulfide Stress Cracking) investigations of duplex stainless steel 2205 resistance to cracking failure under the combined action of tensile stress and aqueous environments containing hydrogen sulfide according to the NACE Standard TM0177-96. The investigations were carried out on 9 test pieces that were loaded with a tensile stress ranging from 1.02 × the yield stress (YS) to 0.72 × YS. The tests were terminated either when the test specimen failed or after 720 h (30 days) - whichever occurred first - in accordance with the standard requirements. Only two of the specimens examined, one loaded with 1.02 × YS and the second one with 0.72 × YS, failed during the test. The resulting fracture surfaces were subjected to qualitative and quantitative fractographic examinations. Quantitative fracture analysis included an estimation of such parameters as linear roughness index R_L, fractal dimension D_F and overlap index O_L.