Evaluación de aceros inoxidables duplex para la construcción de un digestor

the possibility of the construction of a digester for a kraft pulping plant with the evaluation of the performance in relation to stainless steels corrosion was studied. the stainless steels used as working electrodes were: ldx 2101, 2205 and saf 2304, in the three zones, sine of the alloy, weld metal and heat- affected zone (haz). astm standards were applied. the results obtained were provided by the electrochemical impedance spectroscopy technique, together with optical observations. the measurements were carried out in the media specified by the standards and in white liquor, 90 g/l naoh, 40 g/l na2s y 20 g/l na2co3, ph 14 solution, at t= 90-100 oc. alloys suffered attack of the crevice and pit type, or only pit according to the aggressiveness of the medium. the susceptibility of the intergranular attack was different in relation to the alloy and also to the area under study. the duplex stainless steel 2205 appears to be less susceptible to localized corrosion.