Targeted control of microstructure homogeneity of Ni-based superalloy complex component by electric pulse

Thin-walled W cross-section ring of Ni-based superalloy is a critical component for the aerospace and nuclear. The commonly used forming method for this ring easily leads to inhomogeneous microstructure distribution, which is hard to be solved by heat treatment (HT). Electric pulse treatment (EPT) provides a new idea for regulating material's microstructure distribution due to the local Joule heating effect of electric pulse (EP). Here, the comparative study on the microstructure evolution of Ni-based superalloy under HT and EPT was carried out, it was found that EP could provide more electrical energy in the large deformation area and then significantly improve the microstructure distribution of ring component. The mechanism could be attributed to higher electrical resistance in the large deformation area because of higher defects content here, which motivated more pronounced local Joule heating effect.