Manufacturing method of compressor impeller and compressor impeller

Abstract

An object is to provide a manufacturing method of a compressor impeller which produces a small post-cutting residual strain. A compressor impeller is formed by cutting a workpiece. The manufacturing method of a compressor impeller includes: a workpiece-fixing step of fixing a workpiece W on the supporting pedestal; and a cutting step of cutting inter-vane regions R and forming a plurality of vane sections B, Band so on with intervals between one another in the circumferential direction of the workpiece W while pressing the workpiece. The cutting step includes selecting one of following steps. In the first cutting step, when successively cutting the plurality of inter-vane regions R, Rand so on disposed continuously in the circumferential direction of the workpiece, adjacent one of the inter-vane regions is avoided as often as possible. In the second cutting step, when simultaneously cutting a part of the plurality of inter-vane regions R, Rand so on which includes more than one of the inter-vane regions disposed continuously in the circumferential direction of the workpiece, at least one of the part of the plurality of inter-vane regions being cut simultaneously is positioned away from other inter-vane regions being cut simultaneously by a distance of one or more inter-vane regions as often as possible.