Abstract

Austenitic stainless steels, for instance 301, 304, 316L, 321 and 310 are widely used in marine structures and petrochemical industry [1]. Such steels are typically characterized by good ductility and excellent overall corrosion resistance. However, they possess relatively low yield strength (200 to 360MPa), which hinders their structural applications. In the past years martensite treatment including 90 percent cold-rolling followed by annealing treatment in the intervals temperatures of 650 to 800 °C have been applied to produce nano/ultrafine grained steels to improve the yield stress of material without sacrificing ductility [1-4]. The details of formation of nano/ultrafine-grained steels have been discussed in our previous work [1-3]. Table 1 depicts the experimental procedure to fabricate ultrafine-grain steels briefly.