Iron type golf club head

Abstract

Provided is an iron type golf club head having an undercut cavity. The iron type golf club head comprises a face portion () for hitting a ball; a peripheral edge () of the face portion () is provided with a flange portion () protruding backward of the head; a rear surface () of the face portion () is provided with a cavity (C) surrounded by the flange portion (). The flange portion () includes a first flange part (). The first flange part () is provided in its inner surface () side facing to the cavity (C) with a first concave part () dented toward the outside of the head so as to form an undercut cavity (c) extending along the peripheral edge (). The cross-section of the first concave part () comprises a front wall surface () positioned frontward of the head, a rear wall surface () positioned backward of the head, and a bottom surface () smoothly connecting therebetween, and the cross-section is tapered toward the bottom surface (). The angle () formed between the front wall surface () and the rear wall surface () is not less than 10 degrees and less than 30 degrees, and the bottom surface () is formed of a circular arc having a radius (R) of curvature of not less than 1 mm and less than 2 mm.