Method for controlling surface recrystallization of single-crystal directional solidification blade at low cost

The invention relates to a method for controlling surface recrystallization of a single-crystal directional solidification blade at low cost. The method comprises the following steps: S1, wax injection; s2, seeding a crystal strip; s3, mold shell preparation; and S4, a required directional single crystal blade casting blank is prepared. According to the invention, a method for changing the structure of the seeding strip is adopted, so that the seeding strip can be spontaneously broken from the gap of the seeding strip in the solidification and shrinkage process of the alloy component, thereby damaging the integrity between the single crystal alloy component and the seeding strip, and greatly reducing the probability of mutual extrusion between the single crystal alloy component and the mold shell in the solidification and shrinkage process; and therefore, the surface recrystallization defect caused by the solidification shrinkage stress in the casting process of the single crystal alloy component is fundament