Improved nickel aluminide intermetallic alloys for tooling applications

摘要

Castings based on the nickel aluminide intermetallic alloy IC-221M were melted and poured with an addition of enough molybdenum to bring its concentration to 5 weight %. This resulted in a minimization or elimination of the nickel-zirconium eutectic phase in the dies machined and prepared from these castings. The benefit of eliminating or minimizing the nickel zirconium eutectic phase with the addition of measurable amounts of molybdenum (Mo) to the nickel aluminide (Ni3Al) alloy is the increase in the useful service life of the tooling made from it; thus providing the advantages of increased productivity, enhanced quality and reduced costs in a manufacturing setting. Heat treatment of the dies machined and prepared from these castings was also undertaken. The heat treatment regimen includes solution treatment at 2100 DEG F. for 24 hours and aging from between 1150 DEG F. and 1300 DEG F. for between 12 to 24 hours. The benefit of heat treating the dies is the increase in the mechanical properties and hence the service life of the tooling made from it.