Disclosed herein is a casting cluster for casting a body of a golf club head made of titanium or a titanium alloy. The casting cluster comprises a receptor and a plurality of runners coupled to the receptor and configured to receive molten metal from the receptor. The casting cluster also includes at least forty main gates. At least two of the main gates are coupled to each of the runners and each main gate is configured to receive molten metal from a corresponding one of the plurality of runners. The casting cluster further comprises at least forty molds. Each mold of the at least forty molds is configured to receive molten metal from a corresponding one of the main gates and to cast a body of an iron-type golf club head.

Disclosed herein is a casting cluster for casting a body of a golf club head made of titanium or a titanium alloy. The casting cluster comprises a receptor and a plurality of runners coupled to the receptor and configured to receive molten metal from the receptor. The casting cluster also includes at least twenty-eight main gates. At least two of the main gates are coupled to each of the runners and each main gate is configured to receive molten metal from a corresponding one of the plurality of runners. The casting cluster further comprises at least twenty-eight molds. Each mold of the at least twenty-eight molds is configured to receive molten metal from a corresponding one of the main gates and to cast a body of a golf club head that has a volume of at least 100 cm.sup.3.

Disclosed herein is a casting cluster for casting a body of a golf club head made of titanium or a titanium alloy. The casting cluster comprises a receptor and a plurality of runners coupled to the receptor and configured to receive molten metal from the receptor. The casting cluster also includes at least forty main gates. At least two of the main gates are coupled to each of the runners and each main gate is configured to receive molten metal from a corresponding one of the plurality of runners. The casting cluster further comprises at least forty molds. Each mold of the at least forty molds is configured to receive molten metal from a corresponding one of the main gates and to cast a body of an iron-type golf club head.

Disclosed herein is a casting cluster for casting a body of a golf club head made of titanium or a titanium alloy. The casting cluster comprises a receptor and a plurality of runners coupled to the receptor and configured to receive molten metal from the receptor. The casting cluster also includes at least forty main gates. At least two of the main gates are coupled to each of the runners and each main gate is configured to receive molten metal from a corresponding one of the plurality of runners. The casting cluster further comprises at least forty molds. Each mold of the at least forty molds is configured to receive molten metal from a corresponding one of the main gates and to cast a body of an iron-type golf club head.

Nickel-iron-cobalt based alloys are disclosed having sufficient castability for centrifugal casting essentially free from casting defects, cracking, and microstructure variability, and coefficients of thermal expansion up to about 910.sup.6/ C. for about 100-400 C. and increasing from about 400-500 C. to up to about 1010.sup.6/ C., or up to about 610.sup.6/ C. between about 100-300 C. and increasing from about 300-500 C. to up to about 1010.sup.6/ C. Articles are disclosed including unitary cast structures free of internal welds, brazing, and bolting, essentially annular conformations, diameters of at least about 500 mm, cross-sectional wall areas of at least about 2,000 mm.sup.2, and compositions including nickel-iron-cobalt based alloys. Methods for forming the articles are disclosed including rotating centrifugal molds with the compositions in molten states, forming the articles in near net shape.

Nickel-iron-cobalt based alloys are disclosed having sufficient castability for centrifugal casting essentially free from casting defects, cracking, and microstructure variability, and coefficients of thermal expansion up to about 910.sup.6/ C. for about 100-400 C. and increasing from about 400-500 C. to up to about 1010.sup.6/ C., or up to about 610.sup.6/ C. between about 100-300 C. and increasing from about 300-500 C. to up to about 1010.sup.6/ C. Articles are disclosed including unitary cast structures free of internal welds, brazing, and bolting, essentially annular conformations, diameters of at least about 500 mm, cross-sectional wall areas of at least about 2,000 mm.sup.2, and compositions including nickel-iron-cobalt based alloys. Methods for forming the articles are disclosed including rotating centrifugal molds with the compositions in molten states, forming the articles in near net shape.

A method comprises providing a molten aluminum alloy selected from the group consisting of 6000 series aluminum alloys comprises chromium (Cr) in a range of between 0.001 wt % to 0.05 wt %. The molten aluminum alloy is formed into a formed body having beta-AlFeSi particles. The formed body is solution heat treated at a temperature in a range of 1,025-1,050 F. to form a heat-treated body. The solution heat treating transforms substantially all of the beta-AlFeSi particles into alpha-AlFeSi particles such that the heat-treated body is substantially free of the beta-AlFeSi particles.

A method comprises providing a molten aluminum alloy selected from the group consisting of 6000 series aluminum alloys comprises chromium (Cr) in a range of between 0.001 wt % to 0.05 wt %. The molten aluminum alloy is formed into a formed body having beta-AlFeSi particles. The formed body is solution heat treated at a temperature in a range of 1,025-1,050 F. to form a heat-treated body. The solution heat treating transforms substantially all of the beta-AlFeSi particles into alpha-AlFeSi particles such that the heat-treated body is substantially free of the beta-AlFeSi particles.

A cast cup can include a forward portion of a golf club head, including a hosel, a face portion, and forward portions of a crown, sole, heel and toe. A rear ring can be formed separately from the cast cup and coupled to heel and toe portions of the cast cup to form a metallic club head body, such that the club head body defines a hollow interior region, a crown opening, and a sole opening. The cast cup and rear ring can be cast of titanium alloys. Composite crown and sole inserts can then be coupled to the crown opening and sole opening. The face portion of the cast cup can have a desirably complex geometry. The rear surface of the face portion of the cast cup can be modified before the rear ring is attached.

A cast cup can include a forward portion of a golf club head, including a hosel, a face portion, and forward portions of a crown, sole, heel and toe. A rear ring can be formed separately from the cast cup and coupled to heel and toe portions of the cast cup to form a metallic club head body, such that the club head body defines a hollow interior region, a crown opening, and a sole opening. The cast cup and rear ring can be cast of titanium alloys. Composite crown and sole inserts can then be coupled to the crown opening and sole opening. The face portion of the cast cup can have a desirably complex geometry. The rear surface of the face portion of the cast cup can be modified before the rear ring is attached.