Improved tribological properties of laser directed energy deposition repaired Inconel 718 superalloys via heterogeneous microstructures control

High quality repairing is crucial for improving the remaining useful life of wear damaged components. In this work, Inconel 718 superalloys were locally repaired via laser directed energy deposition and then heat treated by the double aging (DA) and homogenization plus DA (HDA). Tribological behaviors of the repaired region which includes both the deposition half and substrate half at light and heavy loads were investigated. Results indicate that the wear resistance of the deposition half determines the wear rate of the repaired region. Moreover, the residual Laves phases improve the abrasion resistant of the DA treated sample at the light load. Meanwhile, the improved ductility through dissolving Laves phases alleviates the delamination wear of HDA treated sample at the heavy load.