Session: 13-04 Thermal Performance of Coatings, Ceramic Composites, and Additively Manufactured Metal Hardware

Paper Number: 102569

102569 - Impacts of Superalloys on the Surface Quality of Additively Manufactured Channels 

Gas turbines feature many components that require superalloys capable of handling extreme thermal environments. Increasing the selection of materials available for these components is important to improving part performance and life. This study investigated two recently developed materials intended to be used for additive manufacturing (AM) with one superalloy based on Cobalt and the other on Nickel. Sets of four test coupons were built using the materials, in addition to the commonly used Inconel-718, on multiple laser powder bed fusion (L-PBF) machines. Several build conditions were varied between coupon sets including coupon orientation, contour settings, and upskin and downskin treatment. Each set of test coupons featured four unique cooling designs to explore how different cooling technologies would be impacted by the variations in build conditions. After being built, coupons were CT scanned to determine accuracy to design intent and quantify the surface roughness. The CT scans indicated that horizontally built test coupons had significantly higher deviation from design intent and higher surface roughness than those built vertically. Results also indicated that the cobalt-based alloy consistently had a smoother surface quality with lower surface roughness compared to the nickel-based alloy. After geometric characterization, the cooling performance of the test coupons was measured experimentally. Pressure losses were found to correlate with increases in surface roughness; however, convective heat transfer did not as a result of surface features significantly blocking the flow without substantially convecting heat.

Presenting Author: Thomas M. Corbett Pennsylvania State University

Presenting Author Biography: Thomas Corbett is a Ph.D. candidate at The Pennsylvania State University, conducting research as a member of the Steady Thermal Aero Research Turbine (START) laboratory. His current research is focused on developing and understanding additively manufactured internal cooling concepts for use in industrial gas turbines. Mr. Corbett was a recipient of the 2020 University Turbine System Research (UTSR) Gas Turbine Industrial Fellowship (GTIF), which gave him the opportunity to apply his research to commercial engines through a research appointment at Solar Turbines Inc.

Authors:

Thomas M. Corbett Pennsylvania State University
Karen A. Thole Pennsylvania State University
Daniel Ryan Solar Turbines Incorporated
Sudhakar Bollapragada Solar Turbines Incorporated
Michael Kirka Oak Ridge National Laboratory
Christopher Ledford Oak Ridge National Laboratory