Effect of Melt Overheating History on the Microstructure of Ni-Base Single Crystal Superalloy
With the unchanged thermal gradient and withdrawal speed, the effect of melt overheating history on the microstructure of Ni-base single crystal superalloy is investigated. The results show that the dendrite structure and γ' phase in interdendritic area is obviously refined when overheating temperature increased from 1500 °C to 1640 °C and then to 1780 °C. However, the microstructure is coarsen with the holding time is increased from 30 min to 45min and then to 60min when melt is overheated at 1780 for 30min.
M.M. Zou et al., "Effect of Melt Overheating History on the Microstructure of Ni-Base Single Crystal Superalloy", Advanced Materials Research, Vols. 217-218, pp. 692-696, 2011