The interdendritic-melt solidification control (IMSC) and its effects on the porosity and phase change of a Ni-based superalloy

A novel interdendritic-melt solidification control (IMSC) technique is developed to manufacture equiaxed Ni-based superalloy with much reduced porosity. The basic concept of IMSC is illustrated. The effects of IMSC on the porosity and phases of IN792 alloy are investigated using quantitative metallography and synchrotron X-ray diffraction. Compared to conventional investment casting, IMSC can produce castings with no shrinkage porosity, much less microporosity and larger dendritic arm spacing, slightly larger sized eutectic (γ + γ′) and MC carbides, and has no significant effects on the relative amount of phases.