The competition concept states that stress corrosion cracking (SCC) can only occur when the crack growth rate exceeds the dissolution ratq moreover, based upon this concept, there also exist a critical temperature for SCC of austenitic stainless steels in chloride solutions where SCC can not occur at or below this temperature. The objectives of this study are to explain both the observed SCC potential region and the SCC critical temperature obtained for 18Cr-14Ni steels by referencing to the competition concept. The SCC potential range was found to be the potential range between the crevice repsssivation potential and the potential where the crack growth rate equals the dissolution rate. The SCC critical temperature was found to be the temperature where the crack growth rate and the dissolution rate intercepts in an Arrhenius plot.
Keywords: stress corrosion cracking, crevice corrosion, stainless steel, alloying effect, phosphorus, dissolution rate, crack growth rate, repassivation potential, critical temperature, copper.