Abstract Scope |
Commercial Ni-based superalloys, NIMONIC® 105, Haynes® 282®, INCONEL® 740H® (IN740H) and INCONEL® 617 (IN617), were investigated to assess their performance in creep when compared to their cast and wrought counterparts. Typically, castings are associated with decreases in time to failure as well as creep ductility. Overall, all but IN740H performed well with properties matching or close to those of the wrought products on a Larson Miller plot. Pathways to improve the creep properties of the castings were explored, including computational homogenization heat treatment, custom aging heat treatments as well as alternative casting routes. Interestingly, a fine grain casting approach improved the creep performance of IN740H by refining the grain boundary phase distribution. A smaller influence of this technique was found for IN617 underlining challenges associated with certain alloy chemistries. More than 70,000 hours of cumulative in-house creep testing (>8 years) on material manufactured using industry relevant techniques will be discussed. |