Microstructure of IN738LC Fabricated Using Laser Powder Bed Fusion Additive Manufacturing

Abstract Nickel-base superalloys are extensively used in the production of gas turbine hot-section components as they offer exceptional creep strength and superior fatigue resistance at high temperatures. Such improved properties due to presence precipitate-strengthening phases such Ni3Ti or Ni3Al (γ′ phases) normally face-centered cubic (FCC) structure solidified nickel. Although this second phase is main reason for improvements properties, also results increased processing difficulties these alloys prone crack formation. In work, specimens IN738LC fabricated on a Coherent Creator laser powder bed fusion (L-PBF) additive manufacturing (AM) equipment. Optical microscopy (OM), scanning electron (SEM), backscatter diffraction (EBSD), X-ray (XRD) carried out characterize deposit region. Metallurgical continuity achieved entire region do not show any warpage. However, voids (e.g., pores cracks) The that percentage void area decreases along build height direction. deposited shows polycrystalline grains confirmed by XRD EBSD. grain size variations summary, open opportunities academic researchers small-scale businesses fabricating high-γ′ nickel-base desktop AM