Abstract: The present invention provides a golf club head comprising: a face section made of a low specific gravity metal not higher than 5; and a back face section made of a clad material in which the low specific gravity metal and a high specific gravity metal not lower than 7 are metallurgically bonded to each other in advance, wherein the low specific gravity metal of the face section and the low specific gravity metal of the clad material are integrally joined to each other by welding so as to form a club head. In this case, the methods of welding of TIG, plasma arc and laser beams are used in which a U-shaped and/or V-shaped groove is formed. In this golf club head, it is possible to improve the mechanical strength of the joint portion, and it is also possible to produce the golf club head in a short period of time.

Abstract: A set of iron golf clubs, in which a grip is disposed at one end and a club head is disposed at the other end of a shaft, the length of the shaft is gradually decreased and the loft angle is gradually increased from a longer iron to a shorter iron, wherein the structure of the club head is made such that a hollow structure is taken for longer irons and a solid structure is taken for shorter irons in which the volume of hollow portion is gradually decreased as the number of the club changes from side of the longer iron to the shorter iron. The sole width of the club head gradually increases as the number of the club changes from the shorter irons to the longer irons.