The invention discloses a method for achieving additive manufacturing high-temperature
alloy grain supernormal coarsening based on
seed crystal guided directional recrystallization heat treatment, and relates to a coarsening method for additive manufacturing high-temperature
alloy grains. The invention aims to solve the technical problem of insufficient high-temperature
creep property caused by small grain size of the existing additive manufacturing
nickel-based high-temperature
alloy. According to the method, the
single crystal layer with target orientation, namely the
seed crystal, is prepared in the additive manufacturing stage, then the
grain boundary of the
seed crystal is continuously heated through the
electromagnetic induction coil in the subsequent heat treatment, forced recrystallization is carried out by taking the seed
crystal as a unique or absolute dominant growth source, namely oriented recrystallization is carried out, so that the growth of other
crystal grains is inhibited, and the yield of the product is improved. And finally, an ultra-large
grain structure with the seed
crystal as the main source is obtained in the additive component, the average grain length of the ultra-large
grain structure can be increased by two or more orders of magnitude compared with the original additive state and reaches the
millimeter level or even the
centimeter level, and the
crystal orientation is highly consistent with the preset seed
crystal orientation.