Tailoring the Properties in Functionally Graded Alloy Inconel 718 Using Additive Technologies

Abstract

A novel method for forming “programmed” mechanical properties in local components of a part by controlling the microstructure of the alloy under additive production is suggested. It is shown that the thermal fields acting during the additive production may be used for manipulating the preferred orientation of the growing crystals and forming different-size grains, which affects the mechanical characteristics. A gradient material from a high-temperature nickel alloy Inconel 718 with coarse elongated grains in the core and fine-grained microstructure in the external shell is produced and shown to possess higher operating characteristics than the alloy fabricated by the conventional process.