An investigation into the effect of cold deformation and annealing on the microstructure evolution of Sanicro super alloy

This paper deals with the evolution of microstructure and mechanical properties in the Fe-29Ni-26Cr-3.77Mo super austenitic alloy after 80 cold rolling and subsequent annealing. detailed characterization was performed by means of OM and X-ray diffraction pattern and tensile test. particular emphasis was laid on cold rolled banded structure and their contribution to creation of heterogeneous lamellar microstructure during subsequent recovery and recrystallization annealing. The unusual retainment of main deformation morphology after recrystallization was interpreted based on the limited oriented growth by strong effect of Mo solute drag effect. The presence of recovered areas at 850 ºC can play major role in the high retained yield strength after partially recrystallization annealing. During fully recrystallization annealing at 950 ºC with fine grains, the optimum mechanical properties were obtained.

Keywords:

Superaustenitic steels , banded structure , solute drag effect , mechanical properties