A method for high-purification preparation of nickel-based superalloys by electron beam layering induced solidification technology

Abstract

The invention discloses a method for high purification preparation for nickel-base superalloy through an electron beam coating induced solidification technology. The method comprises the following steps of 1, raw material preparing, 2, preparing before smelting, and 3, electron beam coating smelting. Nickel-base superalloy cast ingots are prepared by adopting the method, and macrosegregation of the cast ingots is reduced; under the electron beam induced solidification technology, the degree of purity and the metallurgical quality of the cast ingots are improved by a large margin; and engineering preparation of the large-scale cast ingots can be achieved, and the yield of primary product is improved from being less than 70% of a traditional technology to being above 85%.

Description

technical field [0001] The invention relates to a method for high-purification preparation of nickel-based high-temperature alloy by electron beam layering induction solidification technology. Background technique [0002] The purity of nickel-based superalloys has long been a hot topic in the international superalloy industry. Improving the purity is an effective means to fundamentally improve the performance of superalloys. [0003] The current domestic nickel-based superalloy preparation technology is based on vacuum induction melting (VIM), combined with vacuum autoconsumption (VAR) technology and electroslag remelting (ESR) technology, using a dual melting process (VIM+VAR or VIM +ESR) or triple melting process (VIM+ESR+VAR) to prepare alloy ingots. The crucible refractories used in VIM technology will introduce new impurities to cause melt contamination, and the obtained ingots have coarse grains, uneven grains, large shrinkage cavities, and serious solidification seg...

AI Technical Summary

Problems solved by technology

The crucible refractories used in VIM technology will introduce new impurities to cause melt contamination, and the obtained ingots have coarse grains, uneven grains, large shrinkage cavities, and serious solidification segregation; while ESR and VAR technologies, which are secondary smelting technologies, although Significantly improves the legacy of VIM technology, but also leaves a lot to be desired in terms of the metallurgical quality of the ingot

If the smelting and solidification rate of ESR technology is low, the slag absorbs gas and may react with the melt to generate new impurities; the surface quality of the ingot obtained by VAR is poor, and the internal quality of the alloy ingot is poor because the shrinkage cavity cannot be completely eliminated. Impurities are decomposed and regenerated, and will still exist in the alloy in a dispersed form; in addition, the ingots obtained by VAR may have defects such as black spot segregation, white spot segregation, and annual ring segregation

Images