Microstructural Characteristics, Hardness and Tribological Behavior of Additive Manufactured CM247LC Nickel Super Alloy

Nickel superalloys are being used in applications subjected due to its excellent creep and oxidation behavior. The CM247LC nickel based super alloy is considered due to its exceptional combination of high-temperature strength, creep resistance, oxidation/corrosion resistance, and mechanical properties suitable for applications, particularly in the aerospace industry. Though, unfavorable tribological behavior is primary challenge in gas turbine applications. Nickel-based superalloy CM-247LC was manufactured through laser powder bed fusion process under two different conditions. X-ray diffraction analysis (XRD) was carried out to study phases present in as built CM247LC alloy. Microhardness and tribological characteristics were investigated on the as built alloy. XRD spectrum was predominantly observed with γ and γ′ peaks. Presence of γ′ and MC carbides offered strengthening to the as built CM247LC alloy which enhanced the hardness and tribological properties. The wear rate of samples gets increased with increase in load applied during the wear test. Worn out surfaces were examined and it is observed that the predominant type of wear mechanisms as adhesion and abrasion.