JP2002275593A - Head of golf club - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a head of a golf club having an excellent vibration clamping effect and a high corrosion resistance effect. SOLUTION: This head is composed of alloy steel having at least portions of composition components consisting of <0.03 wt.% C(carbon), 0.2 to 0.6 wt.% Si(silicon), <0.15 wt.% Mn(manganese), <0.3 wt.% P(phosphorus), <0.03 wt.% S(sulfur), 10.5 to 13.5 wt.% Cr(chromium), 0.8 to 1.4 wt.% Mo(molybdenum), 0.8 to 1.4 wt.% Al(aluminum), 0.8 to 1.4 wt.% In (nickel), 0.02 to 0.1 wt.% Nb(niobium), <0.01 wt.% N(nitrogen), <0.03 wt.% Cu (copper) and the balance Fe (iron). The alloy steel is subjected to at least one time of vacuum smelting, then no annealing for a specified time at a specified temperature, by which the main crystal structure of the alloy steel is formed to ferrite.

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, and more particularly, to a golf club head having a more excellent vibration damping effect.

[0002]

2. Description of the Related Art In the course of a player hitting a ball with a golf club, most of the generation and transmission of force occurs at the moment the head of the golf club contacts the ball. That is, at the moment when the head hits the ball, a huge impact force and vibration are transmitted from the head via the shaft and finally to the competitor. In order to reduce the influence of a huge force generated at the moment of hitting the ball on the hitting, a head is generally manufactured by using a material having a large damping property. The purpose is as follows.

(A) At the moment when the ball hits, the force of the part is absorbed by the material and the impact force transmitted to the shaft holder decreases, so that the player can use the shaft holder due to the impact force at the moment when the ball hits. Can be reduced, and the probability that the direction in which the ball flies due to the shaft being tilted deviates from the predetermined direction can be reduced. (B) In the process of hitting the ball, the contact time between the ball and the head is extended, which is useful for controlling the ball when hitting.

[0004] Conventional golf club heads are mostly S
It is made of 25C carbon steel, pure magnesium or aluminum to achieve the above purpose. However, the damping characteristics of S25C carbon steel (the composition and main mechanical properties of S25C carbon steel are shown in Tables 2 and 3) are less than ideal (Q ^-1 = 0.5 × 10 ^-2 ). , That is, S2
The damping effect of 5C carbon steel is not very high. Other, S
25C carbon steel has a low corrosion resistance effect and is easily corroded. Pure magnesium or aluminum can provide an excellent anti-vibration effect, but the biggest disadvantages are low strength and difficulty in welding.

[0005]

The conventional golf club head has the following disadvantages. (A) The controllability of the ball when hitting is not good because the vibration stopping effect is not good. (B) Since it has a low corrosion resistance effect, it is easily corroded.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a golf club head which has an excellent vibration stopping effect and a high corrosion resistance effect.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned drawbacks, a golf club head provided by the present invention comprises at least a part of C (carbon) having a composition component of less than 0.03 wt%, from 0.2 to 0.2% by weight. 0.6 wt% Si (silicon), 0.15
Mn (manganese) less than wt%, P less than 0.03 wt%
(Phosphorus), less than 0.03 wt% S (sulfur), 10.5 to 13.5 wt% Cr (chromium), 0.8 to 1.4 wt%
% Mo (molybdenum), 0.8 to 1.4 wt% Al
(Aluminum), 0.8 to 1.4 wt% Ni (nickel), 0.02 to 0.1 wt% Nb (niobium),
N (nitrogen) less than 0.01 wt%, C less than 0.03 wt%
u (copper) and the remainder are made of alloy steel that is Fe (iron), and the alloy steel is subjected to at least one vacuum smelting and a normalizing process at a certain time and at a certain temperature for the main alloy steel. It is characterized in that a fine crystal structure is made into ferrite.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A golf club head according to one embodiment of the present invention achieves the object of the present invention in such a manner that the inventor improves the characteristics of the constituent materials. Before the alloy steel having the characteristics required by the head of the present invention is completed, the inventor previously produced various different elemental components and experimental alloys of comparative examples, and tested various mechanical characteristics, and tested the head of the present invention. It was used as a reference for the production of alloy steel required for

The inventors have created a total of seven experimental alloys (F1 to F7). Table 1 shows the composition and mechanical properties.
Shown in All the test alloys were subjected to vacuum smelting (VIM) in a vacuum induction electric furnace, and the forging temperature was from 950 ° C to 105 ° C.
At 0 degrees, the rolling temperature is between 950 degrees and 1050 degrees. The damping value (Q ^-1 ) of the experimental alloy was tested by the sound frequency vibration method, the excitation voltage was 15 V, the tensile test was performed by a universal material testing machine, and the crystal structure was observed using a light microscope. .

[0010]

[Table 1]

The composition of various experimental alloys based on the numerical values in Table 1
The effect of element on the material properties is as follows. (A) Looking at the crystal structure of the alloy, ferrite iron + parlor
The attenuation values of F5 and F6 belonging to the twin structure of iron iron are low.
(Q^-1= 2.3 × 10^-2And 3.6 × 10 ^-2)
F4 and F7 belonging to other ferrite iron single crystal structures
Value of the alloy (Q^-1= 5.4 × 10^-2And 7.6 ×
10^-2) Are at least twice as high as the twin structure alloy. This is it
As can be seen, the ferrite iron single crystal structure alloy is higher.
It has a strong vibration stopping effect.

(B) Generally speaking, the addition of Cr (chromium) can increase the corrosion resistance of a material. However, according to Table 1, the content of Cr (chromium) is 1
If it exceeds 0 wt%, the damping value of the alloy will increase significantly. F1
And F3, the Cr content was reduced from 12 wt% to 15 wt%.
It can be seen that when the content is increased to wt%, the attenuation value does not increase significantly, but the elongation decreases significantly. Comparing F1 and F6,
When the Cr content is reduced to approximately 10% by weight, the second phase pearlite iron is formed, and the damping value of the alloy is greatly reduced. From this viewpoint, the Cr content is reduced to approximately 12 w
It is preferred to keep it to t%.

(C) When the content of C (carbon) is very low (for example, F2 and F7), its damping properties and other mechanical properties are all excellent, but considering the difficulties of metallurgy, The C content should not be too low;
It is preferable to keep the content at 3 wt% or less. (D) Although the toughness of the material can be improved by adding Ni (nickel), a twin structure of ferrite iron + pearlite iron is easily generated. Compared to F5 and F7, low C
Only when Ni is added under the content, the alloy can generate a single crystal structure of ferrite iron.

(E) Comparing F3 and F4, the addition of Al (aluminum) can increase the damping characteristics of the material. However, if it is too high, a twin structure of ferrite iron + pearlite iron is generated. , Al content is preferably reduced to 1 wt%. (F) When a small amount of Nb (niobium) is added, the crystal grains become finer, so that a content of about 0.04 wt% is relatively appropriate.

(G) Mo (molybdenum) mainly strengthens the crystal base to increase strength and corrosion resistance, but it is generally preferable to limit the content to 1 wt%. (H) If the content of Si (silicon) is too high, the brittleness of the material increases, but if the content is too low, the effect of preventing vibration is affected. Therefore, it is preferable to limit the Si content to 0.35 wt%. .

From the above experimental results, the inventor produced a special alloy steel and named the alloy steel Fekral. Its components are (see Table 2) C (carbon) of 0.001 wt% or less, Si (silicon) of 0.3821 wt%, 0.0801
wt% Mn (manganese), 0.0119 wt% P (phosphorus), 0.0046 wt% S (sulfur), 12.45 wt%
Cr (chromium), 1.219 wt% Mo (molybdenum), 0.942 wt% Al (aluminum), 1.178 wt%
% Ni (nickel), 0.045 wt% Nb (niobium), 0.01 wt% or less N (nitrogen), 0.03 wt% or less Cu (copper), and the remainder is Fe (iron). Said
The metallurgical process of the Fekral alloy steel undergoes at least one vacuum smelting process and then a normalizing process of 950 degrees × 1 hr before use to turn the main crystal structure of the Fekral alloy steel into ferrite.

[0017]

[Table 2]

Table 3 shows the main mechanical properties of the Fekral alloy steel. Table 3 shows the material properties of S25C carbon steel as a control. According to the comparison data of Fekral and S25C,
It has been found that the attenuation value (Q ^-1 = 9.0 × 10 ^-2 ) of the Fekral alloy steel is about 18 times that of S25C (Q ^-1 = 0.5 × 10 ^-2 ). In addition, the properties of the Fekral alloy steel are all remarkably superior to S25C in terms of yield strength, tensile strength, elongation and shrinkage.

[0019]

[Table 3]

The main difference between the two crystal structures is that the attenuation value of the Fekral alloy steel is higher than that of S25C. Said Fekr
The crystal structure of al alloy steel is ferritic iron. According to the theory of materials science, ferritic iron is soft and averages after normalizing the structure, and the vertical force source is easily absorbed at the grain boundaries and easily transferred in the horizontal direction. Stopping characteristics can be improved. Since the main crystal structure of S25C is ferrite iron + pearlite iron, the anti-vibration property is lower than that of the Fekral alloy steel having a ferrite iron single phase structure.

Next, the inventor made the above-mentioned Fekral alloy steel and S
25C was immersed in seawater and tested for its corrosion rate (sample per square meter, weight difference per hour, g / hm ² ). Table 4 shows the experimental results. According to the experimental results,
The amount of corrosion of Fekral alloy steel on the second day was high (0.0231 g
/ Hm ² ), and thereafter, the increase in the amount of corrosion decreases, and after 25 days, the amount of corrosion of the Fekral alloy steel is only 0.0003 g / hm ² , but S25C is corroded and weighs After 18 days, the amount of corrosion decreased to 1% of that of the Fekral alloy steel.
It becomes 0.03 g / hm ² which is 00 times. Thereby, the F
It can be seen that ekral alloy steel has better corrosion resistance.

[0022]

[Table 4]

Next, the inventor manufactured a golf club head using the Fekral alloy steel. The head has a shell, a striking surface, and a neck. The shell and the neck are SUS17-4PH, SUS1
5-5PH, SUS13-8PH, 255 stainless steel or one of pure titanium, titanium alloy, aluminum alloy, and tungsten nickel alloy is adopted, and it is manufactured by using a precision casting method and a forging method. The hitting surface is made of the Fekral alloy steel and has a thickness of 3 mm.
(In practice, the thickness of the hitting surface is 2.5mm to 4mm)
The hardness is approximately from HRB 80 to 90, and the tensile strength is from 50 to 62 kgf / mm ² .

The method of manufacturing the ball striking surface is based on the Fekr
Al alloy steel is made into a plate material, and it is fitted and brazed using a SUS309L welding material (the composition of which is shown in Table 5 below) or bonded and welded to the entire surface of the ball. A fixed installation forms a suitable hitting area.

[0025]

[Table 5]

During welding, the welding result affects the diameter of the welding material and the magnitude of the input voltage. According to the actual operation experience of the inventor, when the diameter of the welding material is 3.2 mm, the input voltage is 90 to 120 A, and when the diameter of the welding material is 4.0 and 5.0 mm, the input voltage is 130 to 120 A, respectively. At 180 A, and 160 to 240 A, the welding effect is most favorable.

Lastly, the golf club head provided by the present invention will be described in the following items. (A) The head of the present invention may manufacture all or a part of the shell using the Fekral alloy steel. (B) The head of the present invention may use the Fekral alloy steel to manufacture all or part of the neck. (C) The head of the present invention may be a wood club head, an iron club head or a push club head.

[0028]

The head manufactured by the above method has the following advantages. (A) Since the Fekral alloy steel is a material composed of a single ferrite iron crystal structure, it has a higher vibration damping effect as compared with other twin structure carbon steel materials (compared to the twin structure S25C carbon steel material). The attenuation value (Q ^-1 ) of the Fekral alloy steel is S
25 times the carbon steel material). Therefore, the head of the present invention can provide a high vibration absorbing effect to increase the stability and success rate of the hit ball, and can also simultaneously improve the controllability of the hit ball.

(B) The Fekr used to manufacture the head of the present invention
Al alloy steel not only provides better anti-vibration effect, but also has high corrosion resistance, so there is no need for a step of plating the surface to increase corrosion resistance as in the conventional material (S25C) in the manufacturing process. The number of processing steps can be reduced, and the manufacturing cost can be reduced.

(C) The head of the present invention may use the Fekral alloy steel for any part of the head according to the needs of the manufacturer. For example, the ball striking surface, shell or neck portion of the head may be formed of the Fekral alloy steel. May be used to manufacture all or a part of them, and it is possible to provide an anti-vibration effect required by the manufacturer.

(D) Since the Fekral alloy steel is basically stainless steel, the welding and joining (soldering or brazing) are all simpler than conventional pure magnesium or aluminum, and the welding strength is high and the success rate is high. Is also higher.

Claims (13)

[Claims] Claims 1. At least in part, C (carbon) with a composition of less than 0.03 wt%, Si (silicon) from 0.2 to 0.6 wt%, Mn less than 0.15 wt%.
(Manganese), less than 0.03 wt% P (phosphorus), 0.0
Less than 3 wt% S (sulfur), 10.5 to 13.5 wt% Cr (chromium), 0.8 to 1.4 wt% Mo (molybdenum), 0.8 to 1.4 wt% Al (aluminum) , 0.8 to 1.4 wt% Ni (nickel);
02 to 0.1 wt% of Nb (niobium), less than 0.01 wt% of N (nitrogen), less than 0.03 wt% of Cu (copper), the rest being Fe (iron) and alloy steel which is an unavoidable impurity. The alloy steel is characterized in that the main crystal structure of the alloy steel is formed into ferrite through at least one vacuum smelting and through a normalizing process at a certain time and at a certain temperature. Golf club head. 2. The golf club head according to claim 1, comprising a hitting surface, wherein said hitting surface is at least partially formed of said alloy steel. 3. The golf club head according to claim 2, wherein said alloy steel is formed on a plate material and provided on said striking surface by welding. 4. The golf club head according to claim 3, wherein a plate material made of the alloy steel is fitted into the hitting surface and installed by brazing. 5. The golf club head according to claim 3, wherein a plate material formed of the alloy steel is entirely adhered to the hitting surface and welded. 6. The welding material used in welding is 0.03
Less than wt% C (carbon), less than 0.08 wt% Si (silicon), 1.0 to 2.0 wt% Mn (manganese), 0.1 wt%
02 wt% P (phosphorus), less than 0.02 wt% S (sulfur), 22.0 to 25.0 wt% Cr (chromium), 1
4. The golf club head according to claim 3, comprising 1.0 to 14.0% by weight of Ni (nickel). 7. The golf club head according to claim 2, wherein the hitting surface is entirely made of the alloy steel and has a thickness of 2.5 mm to 4 mm. 8. The golf club head according to claim 1, further comprising a shell, wherein at least a part of the shell is made of the alloy steel. 9. The shell is made of SUS17-4PH, SUS
The golf club according to claim 1, wherein the golf club is made of one selected from the group consisting of 15-5PH, SUS13-8PH, 255 stainless steel or pure titanium, a titanium alloy, an aluminum alloy, or a tungsten nickel alloy. Head. 10. The golf club head according to claim 1, wherein the shell is formed by a precision casting method and a forging method. 11. The golf club head according to claim 1, further comprising a neck portion, wherein the neck portion is at least partially formed of the alloy steel. 12. The golf club head according to claim 1, wherein the alloy steel has a tensile strength of 50 to 62 kgf / mm ² . 13. The hardness of the alloy steel is HRB80-9.
2. The golf club head according to claim 1, wherein the value is zero.