MANUFACTURING METHOD FOR CASTING HAVING FINE UNIDIRECTIONAL SOLIDIFIED COLUMNAR CRYSTAL STRUCTURE

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method for a casting whose cross-sectional structure orthogonal to the growth direction has the fine unidirectional solidified columnar crystal structure. SOLUTION: Horizontal continuous inverted oscillation for repeating normal/ reverse rotation, wherein while gradually moving upward a solidification interface so that the temperature gradient of a molten metal in the solidification interface becomes 20-1000 deg.C/cm by cooling the molten metal filled in a casting mold directing from the lower part to the upper part, the normal rotation whose maximum angular acceleration is 5 rad/sec2 or more, and the rotation angle is 45 deg. or more is applied to the casting mold filled with the molten metal, then in succession, the reverse rotation of the same condition is applied, or the horizontal intermittent/normal reverse oscillation for repeating the rotation for rotating in the same direction and with the same condition and stopping is imparted.