Dynamic strain aging in Haynes 282 superalloy

¹ GKN Aerospace Engine Systems, R&T Centre, 46181 Trollhättan, Sweden
² Chalmers University of Technology, Department of Applied Physics, 41296 Göteborg, Sweden
³ Chalmers University of Technology, Department of Materials & Manufacturing Technology, 41296 Göteborg, Sweden

^a Corresponding author: magnus.hornqvist@gknaerospace.com; magnus.hornqvist@chalmers.se

Abstract

Haynes 282 is a newly introduced Ni-based superallony, developed to provide a combination of high-temperature mechanical properties, thermal stability and processability. The present contribution investigates the effect of dynamic strain aging (DSA) on the deformation behaviour of Haynes 282 during monotonic and cyclic loading. It is shown that DSA (presumably related to carbon diffusion based on rough estimates of the activation energy) completely dominates the development of the stress during cycling at intermediate temperatures, leading to extensive cyclic hardening and serrated yielding. However, no clear effects on the fatigue life or the resulting dislocation structure could be observed. The tensile properties were not severely affected, in spite of the presence of extensive serrated yielding, although a reduction in ductility was observed in the DSA temperature regime. During monotonic loading at lower strain rates indications of an additional DSA mechanism due to substitutional elements were observed.