20th International Forgemasters Meeting - IFM 2017

Segregation, shrinkage porosity, and coarse dendrite are main problems in heavy forgings due to the ultra-slow solidification process in heavy ingot. Researchers and engineers have put a lot of effort on improving the solidification microstructure but harvest little. If we jump out of the mind of manufacturing heavy forging by heavy ingot, the solution may be found on the continuous slab, which has finer microstructure and less metallurgy defect compared to ingot. In current study, we have proposed a novel method of manufacturing heavy forgings by first building several slabs to a cuboid, and then forging these slabs under vacuum environment into an integrated billet. Finally, the billet is forged into final product. This method propose a novel way of manufacturing heavy forging with less segregation, shrinkage porosity. Several products, such as rotator for nuclear power station, main journal for hydropower station have been produced by such novel method, homogeneous microstructure and uniform mechanical properties have been obtained.