Solidification Structure Refinement of 2205 Duplex Stainless Steel by Pulse Magneto-Oscillation

The influence of pulse magneto-oscillation (PMO) on the solidification structure of 2205 duplex stainless steel (DSS) was investigated. The influences of different treating power on solidification structure were studied by changing the peak current value. The results indicated that PMO treatment can significantly refine the equiaxed grains of 2205 DSS. The as-cast structure without PMO treatment was coarse equiaxed grains. With the increase of the treating power, the grains of 2205 DSS changed into fine equiaxed grains. The grain density increased from 3.5 grains/cm2 to 42 grains/cm2, i.e. the mean diameter of equiaxed grains decreased from 7.1 mm to 1.8 mm. Meanwhile, the grain refinement due to PMO treatment had little effect on ferrite/austenite ratio during the solidification process.