| 摘要 |
<p>PURPOSE: To suppress the occurrence of pinhole defects at the time of casting the head of an iron golf club with a material, such as mild iron, mild steel, low-carbon steel or low-alloy steel, with which the adjustment of a face angle by the player himself is easy. CONSTITUTION: The casting material is melted in a vacuum atmosphere and is cast by vacuum suction in the method for casting the head of an iron golf club with the material, such as mild iron, mild steel, low-carbon steel or low- alloy steel, with which the adjustment of the face angle by the player himself is easy. Thereby, oxygen, etc., penetrated in the material is discharged into the atmosphere during melting. Further, the gaseous components particularly near the surface are discharged by the vacuum suction even at the time of solidification and, therefore, the pinhole defects do not remain near the surface of the casting.</p> |
