Additive Manufacturing: Qualification and Certification: Poster Session
Sponsored by: TMS Additive Manufacturing Committee, TMS: Mechanical Behavior of Materials Committee, TMS: Nanomaterials Committee
Program Organizers: Faramarz Zarandi, RTX Corporation; Jacob Hochhalter, University of Utah; Douglas Wells, NASA Marshall Space Flight Center; Richard Russell, NASA Kennedy Space Center; Mohsen Seifi, ASTM International/Case Western Reserve University; Eric Ott, GE Additive; Mark Benedict, Air Force Research Laboratory; Craig Brice, Colorado School Of Mines; J Hector Sandoval, Lockheed Martin
Tuesday 4:45 PM
November 3, 2020
Room: Poster Hall
Location: MS&T Virtual
Influence of Printing Parameters within the Binder-powder Interaction: Trenton Colton1; Nathan Crane1; 1Brigham Young University
The understanding of binder-powder interaction is crucial to the advancement of several additive manufacturing processes (AM) most notably binder jetting. Attempts have been made to predict saturation levels of parts with simple calculations based on droplet primitives and/or capillary pressure. These methods have lacked clear predictive ability and neglect crucial aspects of printing parameters. The capability of AM to improve depends on this dynamic droplet/powder interaction as the interaction influences dimensional accuracy, print time, and green part strength. Understanding the underlying physics will decrease needed resources for new material implementation in binder jetting. This study reports on the impact of heating and drop velocity, spacing, and interarrival time on the effective binder saturation levels of lines, layers, and multilayer parts. The results show that velocity and droplet size have a strong impact on the effective saturation of a part. However, drying reduces sensitivity of the process to the process parameters.
Post-build Heat Treatment of Wire-arc Additive Manufactured 410 SS for Hardness Tuning: Girish Padhy1; Winston Kam1; Matthew Willard1; James McGuffin-Cawley1; Michael Kottman2; Bradley Barnhart2; Badri Narayanan2; 1Case Western Reserve University; 2Lincoln Electric. Inc
410 stainless steel has applications stemming from its hardenability, wear resistance, and corrosion resistance. Post-processing is often important to optimizing mechanical and corrosion properties. To fully realize the value of additive manufacturing with this alloy, an understanding of the influence of post-build heat treatment on, for example, hardness is necessary. In this study, samples excised from a Wire Arc Additive Manufactured 410 SS block, in as-deposited state and after tempering at various temperatures between 566-787 ᵒC and times between 1-8 h were tested for microhardness. Results indicated that average microhardness (200-380 HV) is independent of build position within each layer and through the stack of layers. By tempering, the microhardness averaged over all layers of the as-deposited block (371±63 HV) decreased by 17-44% and its variance was markedly reduced by 63-95%. Surprisingly, the hardness was only weakly dependent on tempering time, implying that tempering is sufficient after 1 h.