Avaliação da corrosão sob tensão em aço inoxidável AISI 321 em ambiente de reator nuclear

The aim of this work is to evaluate the stress corrosion cracking (SCC) susceptibility of AISI 321 steel under environmental conditions similar to those of a nuclear power plant. The evaluation was performed using the slow strain rate test (SSRT) method, which is one of the most recent techniques developed to evaluate the SCC process in laboratory. The tests were performed under temperature of 288 °C and pressure of 8 MPa, in water environment (containing 1000 ppm of B and 2,2 ppm de Li) and in inert atmosphere (2). The results indicated that the strain rate of 3x10-7 s-1 is adequate to perform comparative evaluations of the SCC process using the SSRT test. They also revealed that the AISI321 steel presents a low susceptibility to SCC for the analyzed conditions.