Abstract:Effects of no treatment, pulsed magnetic field (PMF) treatment, mechanical vibration treatment and compound treatment of pulsed magnetic field and mechanical vibration on the solidified structure and mechanical properties of superalloy K4169 were studied comparatively. Morphologies of primary phase of the alloy with different pulse voltages, pulse frequencies and pouring temperatures under the conditions of compound treatment were investigated. The results show that average grain size of the alloy is refined from 4.5 mm to 0.98 mm, and the fraction of equiaxed grains of the alloy is increased from 36% to 96% by compound treatment. Refinement effect of solidified structure by compound treatment is more efficient than that of pulsed magnetic field treatment or mechanical vibration treatment. Meanwhile, tensile strength and elongation of the alloy with compound treatment compared with the alloy in traditional condition increase by up to 49.2% and 37.3%, respectively. With the increase of the pulse voltage or frequency, primary phase of the alloy degrades gradually from well-developed dendrites into fine equiaxed grains or rosette crystals. When the pouring temperature is 1380~1530 °C, the increase of pouring temperature enhances the refinement effect of compound treatment