JPH11151326A - Golf club head and manufacture of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the strength and to increase the hitting distance of a ball by forming at least a part of a face part of a club head, by a member made of an alloy of a material comprising a supercooled liquid and producing the metal glass, and shaped by the molten bath forging. SOLUTION: At least a part of a face part of a club head is formed by a member made of an alloy of a material comprising the supercooled liquid and producing the metal glass, and formed by the molten bath forging. This member is provided with a metallographic structure comprising an amorphous phase and a crystalline phase by heat treated at a temperature of a glass transition point (Tg) ±50 K of the alloy of the material comprising the supercooled liquid and producing the metal glass, whereby the strength can be improved. As the alloy of a composition comprising the supercooled liquid and generating the metal glass, the alloys such as Pd-Ni-Cu-P, Zr-Al-Ni-Cu, Zr-Al-Ni-Cu-Pd or the like can be included.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a golf club head having excellent strength and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, it has been desired to form at least a part of a face of a golf club head from a titanium alloy. This is because the properties of titanium alloy, such as low specific gravity and high strength, are generally considered to be suitable for head materials. However, it has been recognized that the low Young's modulus of the titanium alloy is particularly advantageous in addition to the characteristics of low specific gravity and high strength.

[0003] The face of a golf club head is deformed when the ball is hit. If the face can be restored to its original state without permanent deformation at this time, the larger the face deformation, the larger the ball deformation. It can be expected to increase the flight distance. It is considered that a material having a low Young's modulus is ideal as a material whose face is greatly deformed. Japanese Patent Application Laid-Open No. 9-187534 proposes a golf club head having a face made of metallic glass. Since metallic glass (amorphous metal or amorphous metal) has higher strength than titanium alloy and higher elastic limit than conventional metal, the golf club head according to this publication uses titanium alloy as a material. Attention is paid to the fact that the ball can be expected to fly farther than the head that was hit.

[0004]

However, in this publication, the molten metal for producing metallic glass is rapidly cooled,
It merely discloses obtaining a metal structure having an amorphous single-phase structure by solidification.

According to the present invention, strength is improved by obtaining a metal structure of an amorphous phase and a crystalline phase, instead of using an alloy for forming metallic glass as a material and forming an amorphous single phase. It is an object of the present invention to provide a golf club head which can be further improved and can expect a ball to fly far away, and a method of manufacturing the same.

[0006]

A golf club head according to the present invention has at least a part of a face having a supercooled liquid region, is made of an alloy having a composition for producing metallic glass, and is formed by melt forging. It is composed of a member, and the member has a metal structure of an amorphous phase and a crystalline phase.

In the method of manufacturing a golf club head according to the present invention, a member constituting at least a part of the face is
An alloy having a supercooled liquid region and producing a metallic glass is used as a material, formed by melt forging, and the member is subjected to a heat treatment at a temperature of glass transition temperature (Tg) of the alloy ± 50K. I do.

In the present invention, the golf club head comprises:
At least a member constituting a part of the face has a supercooled liquid region and is made of an alloy having a composition for generating metallic glass. The supercooled liquid region is the temperature at which the alloy begins to crystallize (T
x) and the glass transition temperature (Tg) ΔTx (= T
(x-Tg), an alloy having a composition that produces a metallic glass having this supercooled liquid region can produce metallic glass even after being heated and melted and then cooled at a relatively low speed. Pd-Ni-Cu-P and Zr-Al-N are alloys having a composition that produces a metallic glass having a supercooled liquid region.
i-Cu, Zr-Al-Ni-Cu-Pd, La-Al
-Ni, La-Al-Ni-Cu, Mg-Y-Cu, Z
r-Ti-Ni-Cu-Be, Pr-Fe-Al, Nd
-Fe-Ga based alloys are exemplified. Of these, the larger the temperature range of the supercooled liquid region, the easier it is to process using the high viscosity that appears in the supercooled liquid region, and the easier it is to dispose even if the processing varies. A crystalline phase can be obtained.

[0009] In the present invention, Zr55Cu30Al10Ni5 Zr55Cu30Al10Ni3Co2 Zr55Cu30Al10Co3Fe2 Zr55Cu30Al10Ni4Pd1 Zr55Cu30Al10Ni4Au1 Zr55Cu15Ni10Al15Ti5 Zr53Cu19Ni13Al10Ti5 Zr60Cu22Al10Au8 Zr60Cu20Al10Pd10 Zr60Cu25Al10Pt5 Zr65Cu12.5Al7.5Ni10Ag5 (numbers atomic%) can be preferably used, and the like.

In order to form a member constituting at least a part of the face by using an alloy having a composition for producing metallic glass having a supercooled liquid region, a method of forging molten metal is employed. The molten metal forging may be any method as long as the molten alloy is pressurized and spread in a pair of upper and lower dies and solidified, but needs to be cooled and solidified at an appropriate speed to obtain an amorphous phase. In the present invention, the cooling rate is 1 to 100 K / sec.
Perform in the range of c.

Here, for example, the alloy can be heated and melted on a lower mold in an atmosphere of an inert gas such as Ar gas or the like. Therefore, it is not easy to prevent crystallization. For this reason, it is difficult for the member to be formed to have an amorphous single-phase metal structure, and the contact surface portion with the lower mold, that is, the surface portion of the member becomes almost only a crystalline phase, and becomes brittle, resulting in a golf ball. Not good for club heads. A portion suitable for a golf club head is a portion obtained by spreading and solidifying a molten metal of an alloy not in contact with the lower mold. This part is an amorphous phase that does not contain a crystalline phase,
In the present invention, a very fine crystalline phase (nanocrystalline phase) is dispersed and generated in such an amorphous phase by a heat treatment or the like, and is used for at least a part of the face. It has been found that a golf club head with increased strength can be obtained.

The method of manufacturing a golf club head according to the present invention can be manufactured by forming at least a part of the face by melt forging and then performing a heat treatment. In the heat treatment, the formed member is heated to a temperature of a glass transition temperature (Tg) of the material ± 50 K in an inert gas atmosphere such as an Ar gas, and is heated for 1 to 100 minutes.
It is preferably carried out for 10 to 30 minutes.
Cool in the range of 100 K / sec. At a temperature higher than the crystallization start temperature (Tx), crystallization proceeds very quickly, and the material becomes brittle at a temperature higher than the vicinity of the crystallization start temperature (Tx). This is because it takes a long time for the production, and the mass productivity is deteriorated. In the case of manufacturing by heat treatment in this way, the entire member has a metal structure in which a crystalline phase is dispersed. In the present invention,
By heat-treating the surface of the member by induction hardening, the crystalline phase can be dispersed and generated only on the surface of the member.

[0013]

EXAMPLE An alloy having the following composition was used as a material, and a face of a wood club head was formed by melt forging and heat-treated. The body portion of the wood club head excluding the face was formed by precision casting from stainless steel, and the face was fixed to this body portion to produce the golf club head of the present example. Alloy composition used : Zr55Cu30Al10Ni5 Crystallization start temperature (Tx): 755K Glass transition temperature (Tg): 670K Supercooled liquid region (ΔTx): 85K To produce a face with a thickness of about 2 mm, 120 g
In an arc voltage of 20 V and an arc current of 300 A, the alloy is sufficiently arc-melted, and at a pressure of 5 kgf / cm ² ,
The melt was forged at a mold closing speed of 50 mm / sec. Then, at a temperature of 670 K in an Ar gas atmosphere, 3
Heat treatment was performed for 0 minutes, followed by rapid cooling.

The cast material of the alloy used in this embodiment, the unheated molten forged material, and the heat treatment (30 ° C at a temperature of 670 K)
Table 1 shows the physical properties of the molten forged material subjected to the above-described processes.

[0015]

[Table 1]

The heat-treated forged material has a higher tensile strength than the cast material and the forged material (not heat-treated), and has a high strength.

Table 2 shows the results of a test hit between a wood club (1 W) having a shaft attached to the golf club head of the present embodiment and a wood club (1 W) made of a titanium alloy head. The test hit was performed using a swing robot device, and the club head speed (Hv) was 45 m / sec.
And the ball was hit at 40 m / sec, and the initial velocity efficiency, launch angle, carry and distance were measured. The initial speed efficiency is a ratio of the speed immediately after the ball is launched to the club head speed.

[0018]

[Table 2]

[0019]

According to the present invention, at least a part of the face of the golf club head has high strength, and
Since it has a metal structure of an amorphous phase and a crystalline phase having a higher elastic limit than conventional metals, it is expected to have excellent strength and to fly the ball far away.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Katsumi Yamano Inventor 5412 Shido, Shido-cho, Okawa-gun, Kagawa Prefecture (72) Inventor Kazunobu Nozaki 5412 Shido, Shioji-cho, Okawa-gun, Kagawa Prefecture Casco Co., Ltd. Inside

Claims (3)

[Claims] At least a part of the face has a supercooled liquid region, is made of an alloy having a composition for producing metallic glass, and is formed of a member formed by melt forging, and the member is made of an amorphous material. A golf club head comprising a metal structure of a phase and a crystalline phase. 2. The golf club head according to claim 1, wherein the member has a metal structure in which the whole or surface portion has an amorphous phase as a base and a crystalline phase is dispersed in the base. A golf club head characterized by the following. 3. A member constituting at least a part of the face is made of an alloy having a supercooled liquid region and a composition for producing metallic glass, and is formed by molten forging. A method for manufacturing a golf club head, wherein a heat treatment is performed at a temperature (Tg) of ± 50K.