Abstract:The effect of multi-electromagnetic field on the K417 superalloy ingots solidification microstructure has been studied. The results show that during the solidification process of superalloy vacuum casting, the application of the multi-electromagnetic field, composed of rotary electromagnetic field with 60 A current and steady DC electromagnetic field with 290 A current, can increase the scope and effect of rotary electromagnetic field as well as improve the feeding conditions of ingots. The reason can be attributed to that the electromagnetic brake generated by DC electromagnetic field can suppress effectively the metal surface fluctuation generated by rotary electromagnetic field. As a result, the fine equiaxed grain fraction of ingots can be increased to 96 % and the shrinkage porosity of ingots can be greatly reduced