Process development for laser powder bed fusion of GRCop-42 using a 515 nm laser source

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Samira Gruber - , Fraunhofer-Institut für Werkstoff- und Strahltechnik (Autor:in)
  • Lukas Stepien - , Fraunhofer-Institut für Werkstoff- und Strahltechnik (Autor:in)
  • Leonid Gerdt - , Fraunhofer-Institut für Werkstoff- und Strahltechnik (Autor:in)
  • Elena Lopez - , Fraunhofer-Institut für Werkstoff- und Strahltechnik (Autor:in)
  • Jan Kieser - , Fraunhofer-Institut für Werkstoff- und Strahltechnik (Autor:in)
  • Frank Brueckner - , Fraunhofer-Institut für Werkstoff- und Strahltechnik, Luleå University of Technology (Autor:in)
  • Christoph Leyens - , Professur für Werkstofftechnik, Fraunhofer-Institut für Werkstoff- und Strahltechnik (Autor:in)
  • Craig Bratt - , Fraunhofer USA, Inc. (Autor:in)

Abstract

Copper is widely used in high heat flux and electrical applications because of its excellent electrical and thermal conductivity properties. Alloying elements such as chromium or nickel are added to strengthen the material, especially for higher temperatures. Cu4Cr2Nb, also known as GRCop-42, is a dispersion-strengthened copper-chromium-niobium alloy developed by NASA for high-temperature applications with high thermal and mechanical stresses such as rocket engines. Additive manufacturing (AM) enables applications with complex functionalized geometries and is particularly promising in the aerospace industry. In this contribution, a parametric study was performed for GRCop-42 and the AM process laser powder bed fusion (PBF-LB/M) using a green laser source for two-layer thicknesses of 30 and 60 µm. Density, electrical conductivity, hardness, microstructure, and static mechanical properties were analyzed. Various heat treatments ranging from 400 to 1000 °C and 30 min to 4 h were tested to increase the electrical conductivity and hardness. For both layer thicknesses, dense parameter sets could be obtained with resulting relative densities above 99.8%. Hardness and electrical conductivity could be tailored in the range of 103-219 HV2 and 24%-88% International Annealed Copper Standard (IACS) depending on the heat treatment. The highest ultimate tensile strength (UTS) obtained was 493 MPa. An aging temperature of 700 °C for 30 min showed the best combination of room temperature properties such as electrical conductivity of 83.76%IACS, UTS of 481 MPa, elongation at break (A) at 24%, and hardness of 125 HV2.

Details

OriginalspracheEnglisch
Aufsatznummer042078
FachzeitschriftJournal of laser applications
Jahrgang35
Ausgabenummer4
PublikationsstatusVeröffentlicht - 1 Nov. 2023
Peer-Review-StatusJa

Schlagworte

Schlagwörter

  • additive manufacturing, copper alloys, GRCop alloys, green laser, heat treatment, laser powder bed fusion