Influence of Composition on Continuous Cooling Sensitization of Type 304 Stainless Steel

This study focuses on the influence of composition (primarily the carbon content) on continuous cooling sensitization. The carbon content dependence of the critical cooling rate for sensitization has been determined. Furthermore, the influence of the peak temperature on the carbon content dependence of the critical cooling rate has also been determined. These experiments employ both the 10% oxalic acid test (ASTM A262 Practice A) and the modified Strauss test (ASTM A262 Practice E) to define the critical cooling rate. It was shown that the value of the critical cooling rate for sensitization (a parameter which can be used to determine the degree of weld sensitization or the sensitization to be expected as the result of slow cooling after annealing) depended on the test used to measure the sensitization, the carbon content of the steel, and the peak temperature reached prior to cooling.