The effect of magnetic field on precipitation phases of single-crystal nickel-base superalloy during directional solidification

摘要

The effect of magnetic field on precipitation phases in directional solidified single-crystal nickel-base superalloy was investigated. The magnetic field significantly decreases the size of γ' and the content of carbides and γ/γ' eutectic. The decreased magnitude is firstly sharp and then gentle with the increasing magnetic field intensity. The γ' phase refinement could be attributed to a decrease in nucleation activation energy during solid phase transformation. The segregation reduction of alloying elements is responsible for the content decrease of carbides and γγ' eutectic. The magnetic- field-assisted directional solidification provides an effective way to control the size and content of precipitation in superalloys.