Functionally Graded Materials Manufactured by Direct Energy Deposition: A review

Abstract

This research review paper primarily covered definition, brief historical development, classifications, advantages, disadvantages and applications of metallic Functionally Graded Materials (FGM’s). The FGM’s are classified based on conventional and Additive Manufacturing (AM) methods. Based on the literature most of the FGM’s are manufactured by Direct Energy Deposition (DED) process. But in case of materials consideration for FGM’s fabrications, 68% of stainless steels are processed by Powder Bed Fusion (PBF) and only 28% using DED. The secondary focus is on recent research work on FGM’s processed by DED using stainless steels and nickel based super alloy powders. At last hybrid AM, 4D printing, sustainability of AM, Industry 4.0, and future prospects of FGM’s are discussed.