Investigation on Thermomechanical Treatment of PM FGH4096 Superalloy
Thermomechanical treatment (TMT) of PM FGH4096 superalloy were carried out to futher improve the mechanical strength and refine the γ’ particle, and this processing route as follows: near-isothrmal forged at deformation temperature of 1130°C and strain rate of 0.1 s-1, followed by subsequence oil quenching, and then held at 760°C for 16 h. OM, SEM and TEM were used to investigate the microstructure of TMTed alloy. It was found that the advanced mechanical strength originated form the dispersion strengthening of fine γ’ particle and stain hardening reserved from deformation after TMT. But TMT had no obvious effect on improving the chemical segregation of original materials. Fracture analysis of TMTed alloy shown that cracks origined from Ti and Nb chemical segregation and presented rose-pattern and ladder-pattern at room temperature and 750°C temperature.
Zhengyi Jiang and Chunliang Zhang
Y. Q. Ning et al., "Investigation on Thermomechanical Treatment of PM FGH4096 Superalloy", Advanced Materials Research, Vols. 97-101, pp. 255-259, 2010