| 摘要 |
<p>There is provided a Ti alloy hollow club head which is more lightweight yet capable of realizing a better repulsion force by adjusting weight and thickness of a club head plate, with its strength ensured. Ribs are formed by chemically polishing the inner surface of a material of a crown plate to a 0.3 to 0.9 mm thickness, and a 0.3 to 4 mm width, and then first concave portions are formed to a 0.2 to 0.5 mm thickness. Thus, strength of the crown plate can be ensured by the ribs, while making the thickness thereof as thin as possible.</p> |
