Flow behavior and hot workability of FGH4096 superalloys with different initial microstructures by using advanced processing maps

The flow behavior and hot workability of FGH4096 superalloys with different initial microstructures are investigated in this paper. The study alloys behave different flow behaviors due to different initial microstructures (hot isostatic pressed (HIPed) and fine grained (FGed) microstructures). At 1050 °C, FGed alloy shows higher flow stress than HIPed alloy. At high temperature (1080–1140 °C), however, FGed alloy has lower flow stress than HIPed alloy. Meanwhile, the studied alloys have different hot workability. To investigate the hot workability, advanced processing maps are built up and employed to study the workability. In animation map created in this research, the evolution can be classified into three characteristics, viz., (i) mountain formation, (ii) ridge formation, and (iii) instability domain movement. The motion “vector” (from initial point (HIPed) to terminal point (FGed)) is in the directions of falling temperature (Td ↓) and raising strain rate (ε˙↑), and this “vector” predicts the enhancement of hot workability.

► Flow behavior and hot workability have been investigated on FGH4096 superalloy.
► Reduced isodynamic strength temperature (RIS temp.) is predicted in 1050–1080 °C.
► P-maps movement “vector” predicts the improvement of hot workability.
► RIS temperature and P-maps movement “vector” are new findings.