US20090082133A1

US20090082133A1 - Plating layer structure of golf club head and forming method thereof

Info

Publication number: US20090082133A1
Application number: US11/902,317
Authority: US
Inventors: Yung-Fu Tseng
Original assignee: Fu Sheng Industrial Co Ltd; Nelson Precision Casting Co Ltd
Current assignee: Fu Sheng Industrial Co Ltd; Nelson Precision Casting Co Ltd
Priority date: 2007-09-20
Filing date: 2007-09-20
Publication date: 2009-03-26

Abstract

A plating layer structure of a golf club head and a forming method thereof are disclosed. The forming method comprises: forming a medium layer on the surface of the golf club head; and electroplating a plating layer on the medium layer, wherein the material of the coating layer is electroplating-compatible with the material of the medium layer.

Description

FIELD OF THE INVENTION

This invention relates to a plating layer structure of a golf club head and a forming method thereof, and more particularly, to a plating layer structure of a golf club head with a medium layer and a forming method thereof.

BACKGROUND OF THE INVENTION

Current golf club heads are made of composite materials. In particular, the body and the striking plate of a golf club head are made from different materials. For example, the body can be made from 17-4PH stainless steel, and the striking plate can be made from 6Al-4V titanium alloy, thereby providing a golf club head having a body of high strength and a striking plate of excellent deformability.
For preventing ustiness or corrosion and improving appearance, a cladding material is formed on the surface of the golf club head to reduce the possibility of rusting and corrosion and improve the appearance thereof.
However, when using an electroplating method to form a plating layer on the golf club head with composite materials, in light of electrochemistry theory, the plating layer cannot directly be formed on some specific material, such as aluminum, titanium or nonmetallic materials. Therefore, the adhesion between the plating layer and the golf club head with composite materials (such as aluminum, titanium or nonmetallic materials) is poor, and the corrosion-resistance, rust-resistance or appearance of the golf club head cannot be enhanced.

SUMMARY OF THE INVENTION

Therefore, an aspect of the present invention is to provide a plating layer structure of a golf club head and a forming method thereof to electroplate a plating layer on the golf club head.
Another aspect of the present invention is to provide a golf club head with a plating layer structure, wherein the golf club head has the material that is not electroplating-compatible with the plating layer.
According to an embodiment of the present invention, the plating layer structure of the golf club head comprises a medium layer and a plating layer. The medium layer is formed on the surface of the golf club head. The plating layer is formed on the medium layer, wherein at least a portion of the material of the golf club head is not electroplating-compatible with the material of the plating layer, and the material of the plating layer is electroplating-compatible with the material of the medium layer.
According to another embodiment of the present invention, the method for forming the plating layer structure of the golf club head comprises: forming a medium layer on the surface of the golf club head; and electroplating a plating layer on the medium layer, wherein at least a portion of the material of the golf club head is not electroplating-compatible with the material of the plating layer, and the material of the plating layer is electroplating-compatible with the material of the medium layer.
Therefore, with the application of the plating layer structure of the golf club head and the forming method thereof disclosed in the embodiments of the present invention, the plating layer structure can be electroplated on the golf club head by the medium layer, thereby enhancing corrosion-resistance, rust-resistance and the appearance thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a schematic flow diagram showing the process for forming a plating layer structure of a golf club head according to a first embodiment of the present invention;

FIG. 2 is a schematic front view showing a golf club head according to a first embodiment of the present invention;

FIG. 3 is a cross-sectional diagram showing a golf club head according to a first embodiment of the present invention;

FIG. 4 is a cross-sectional diagram showing a golf club head according to a second embodiment of the present invention; and

FIG. 5 is a cross-sectional diagram showing a golf club head according to a third embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In order to make the illustration of the present invention more explicit and complete, the following description is stated with reference to FIG. 1 through FIG. 5.
Refer to FIG. 1 through FIG. 3. FIG. 1 is schematic flow diagrams showing the process for forming a plating layer structure of a golf club head according to a first embodiment of the present invention. FIG. 2 is a schematic front view of a golf club head according to a first embodiment of the present invention. FIG. 3 is a cross-sectional diagram showing a golf club head according to a first embodiment of the present invention. The forming method of the plating layer structure of a golf club head 100 comprises: surface treating the surface of the golf club head 100 (step 101); forming a medium layer 200 on the surface of the golf club head (step 102); surface treating the surface of the medium layer 200 (step 103); and electroplating a plating layer 300 on the medium layer 200 (step 104), wherein the material of the plating layer 300 is electroplating-compatible with the material of the medium layer 200. Therefore, the plating layer 300 can be firmly formed on the golf club head 100 by forming the medium layer 200 between the golf club head 100 and the plating layer 300, thereby enhancing corrosion-resistance, rust-resistance or appearance of the golf club head 100.
Refer to FIG. 2 and FIG. 3 again. The golf club head 100 of this embodiment may be a wood-type golf club head or an iron-type golf club head, and comprises a main body 110 and a striking plate 120. The striking plate 120 is disposed on the front side of the main body 110 for striking the golf ball (not shown). The golf club head 100 has at least a portion of the material that is not electroplating-compatible with the material of the plating layer 300.
Refer to FIG. 2 again. The material of the main body 110 of this embodiment may be carbon steel (such as S20 or 8620 carbon steel), stainless steel (such as 303, 316 or 17-4PH stainless steel), alloy steel, Fe—Mn—Al alloy, Ni-based alloy, cast iron, titanium alloy (such as CPTI or Ti6Al4V alloy), aluminum alloy, Al—Mg alloy, tungsten alloy, copper alloy, ceramics, carbon fiber, plastics or any composition thereof, and particularly the material is not electroplating-compatible with the material of the plating layer 300 (such as Fe—Mn—Al alloy, ceramics, aluminum alloy, Al—Mg alloy, carbon fiber or plastics). The main body 110 may be made to form one-piece using a method such as casting, precision casting, die-casting, forging or machining, or assembling the segments thereof to form the one-piece. The main body 110 includes a toe portion 111, a heel portion 112 and a hosel 113. The toe portion 111 and the heel portion 112 are respectively located at both ends of the main body 110. The hosel 113 extends out one side of the main body 110 and is close to the heel portion 112 to receive a club shaft (not shown).
Refer to FIG. 2 again. The striking plate 120 of this embodiment is bonded to the front side of the main body 110 by such as a method of inserting, press bonding, brazing, welding or screwing for striking the golf ball. The material of the striking plate 120 may be carbon steel, stainless steel (such as 17-4PH stainless steel), Fe—Mn—Al alloy, titanium alloy (such as CPTi or Ti6Al4V alloy), aluminum alloy, copper alloy, ceramics, carbon fiber, plastics or any composition thereof, and preferably the material with high coefficient of restitution (COR) or high hardness, and particularly material that is not electroplating-compatible with the material of the plating layer 300 (such as Fe—Mn—Al alloy, ceramics, aluminum alloy, Al—Mg alloy, carbon fiber or plastics). The hardness of the striking plate 120 (such as titanium alloy) is preferably higher than the hardness of the main body 110 (such as stainless steel), thereby improving the striking efficacy and distance of the golf club head 100.
Refer to FIG. 1 and FIG. 3 again. When forming the plating layer structure of the golf club head 100, first, a surface treatment step (step 101) is employed on the surface of the golf club head 100 for cleaning the surface of the golf club head 100. During the surface treatment step 101, the surface of the golf club head 100 is first cleaned with ultrasonic energy. When cleaned with ultrasonic energy, the surface of the golf club head 100 is placed in an ultrasonic machine and treated with high frequency ultrasonic waves to remove large grime particles. In the ultrasonic machine, the entire surface of the golf club head 100 is soaked in a solution selected from a group consisting of softened water, alcohol or an organic solvent, such as methanol, ethanol, methyl benzene, acetone or bromine propane. Preferably, the ultrasonic machine generates ultrasonic waves in the frequency ranging from 16 kHz to 60 kHz to vibrate the solution. The ultrasonic energy cleaning step can preliminary remove larger grime particles accumulated on the surface of the golf club head 100. Then, the surface of the golf club head 100 is further cleaned in water.
After the ultrasonic energy cleaning step, the surface of the golf club head 100 is further cleaned using ultrasonic energy and a basic solution for at least one process, thereby heat-degreasing the surface of the golf club head 100. During the heat-degreasing step, the surface of the golf club head 100 is soaked in a basic solution that transmits ultrasonic waves generated from the ultrasonic machine to vibrate the basic solution. Preferably, a frequency of the ultrasonic wave ranges between 16 kHz and 60 kHz. More preferably, the basic solution (such an alkaline solution or an acidic solution) is heated to a temperature between 40 degrees centigrade and 85 degrees centigrade and has a concentration ranging between about 30 percent and 85 percent. More preferably, the basic solution is selected from a group consisting of sodium hydroxide, sodium carbonate, sodium silicate, sodium phosphate, sodium bicarbonate, sodium sulfate, sodium phosphite and mixtures thereof. More preferably, the basic solution is added a desired surfactant—anionics or non-ionics. In electrochemistry, a high-concentrated basic solution is able to remove an oxidative layer (such as Al₂O₃) and grease, and to activate the surface of the golf club head 100. Meanwhile, the ultrasonic energy is able to speed the reactive rate of activating. Accordingly, the ultrasonic energy can maintain activation of the surface of the golf club head 100 to prevent inactivation that may improve adhesion of a cladding material and the plating quality. To solve the high-concentrated basic solution and ultrasonic energy causing a pitting effect on the surface of the golf club head 100, the processing time for the heat-degreasing step ranges between 3 min and 20 min that can prevent excessive corrosion on the surface thereof. Then, the surface of the golf club head 100 is further cleaned in water.
Further, when the basic solution is an acidic solution, the basic solution can remove rust (formed by heating process or tempering process), oxide, hydroxide, or salt. The basic solution is selected from a group consisting of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, hydrofluoric acid and mixtures thereof, and has a concentration ranging between about 5 percent and 30 percent. More preferably, the basic solution is processed at the current density of about 3˜10 A/dm². The processing time for the heat-degreasing step ranges between 30 sec and 20 min, thereby preventing an excessive soakage causing pitting and discoloring on the surface of the golf club head 100. Then, the surface of the golf club head 100 is further cleaned in water.
Next, an electrolysis step removes the remaining oxidative layer and grease, and reactivates the surface of the golf club head 100. In the electrolysis step, the surface of the golf club head 100 is placed in an electrobath to be selectively treated with anodic or cathodic electrolysis. Preferably, a basic solution is used for electrolysis and has a concentration ranging between about 20 percent and 80 percent. More preferably, the acid solution is selected from a group consisting of sodium hydroxide, sodium carbonate, sodium silicate, sodium phosphate, sodium bicarbonate, sodium sulfate, sodium phosphite and mixtures thereof. More preferably, the basic solution is added a desired surfactant, such as anionics or non-ionics. More preferably, the basic solution is heated at a temperature ranging between 40 degrees centigrade and 85 degrees. The surface of the golf club head 100 connected to a cathode generates reaction gas so as to remove oxidative layers, grease and impurities after conducting an electric current. To prevent excessive corrosion which has a pitting and discoloring effect on the surface of the golf club head 100, the processing time for the electrolysis step ranges between 1 min and 3 min. Then, the surface of the golf club head 100 is further cleaned in water.
Further, after the electrolysis step, an acid solution neutralizes the basic solution remaining on the surface of the golf club head 100 so as to prevent excessive corrosion causing a pitting effect. In the neutralizing step subsequent to the electrolysis step, the surface of the golf club head 100 is soaked in the acid solution for a period less than 1˜3 min. Preferably, the acidic solution has a concentration less than 10 percent, and is selected from a group consisting of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, hydrofluoric acid and mixtures thereof. More preferably, the acid solution is heated in a temperature ranging from 20 degrees centigrade to 50 degrees. Then, the surface of the golf club head 100 is further cleaned in water.
Next, an underlayer process is employed. The surface of the golf club head 100 is soaked in the nickel chloride and hydrochloric acid solution for 1˜3 min. Therefore, the surface treatment step 101 is achieved.
Next, the medium layer 200 is formed on the surface of the golf club head 100 (step 102). The medium layer 200 is formed with physical vapor deposition (PVD), such as evaporation deposition, ion plating or sputtering deposition. The material of the medium layer 200 may be stainless steel (such as 303, 316 or 17-4PH stainless steel), Au or Al which is electroplating-compatible with the material of the plating layer 300, i.e. the plating layer 300 can be electroplated straight on to the medium layer 200, wherein the thickness of the medium layer 200 is substantially between 0.3 μm and 1.2 μm. Since the medium layer 200 is formed by the method of PVD, the medium layer 200 can be formed on the surface of the golf club head 100 with nonmetallic material, such as ceramics, carbon fiber or plastics, thereby improving the suitability for the material of the golf club head 100.
It is worth mentioning that the medium layer 200 of this embodiment is formed on at least one portion of the surface or the whole surface of the golf club head 100, wherein the surface covered by the medium layer 200 of the golf club head 100 has material that is not electroplating-compatible with the material of the plating layer 300. Therefore, the medium layer 200 is formed on a portion surface or whole surface of the golf club head 100. For example, when the material of the main body 110 is stainless steel, and the material of the striking plate 120 is titanium alloy, the medium layer 200 is at least formed on the entire surface of the striking plate 120, thereby allowing the plating layer 300 to be electroplated on the golf club head 100.
Refer to FIG. 1 and FIG. 3 again. Next, a surface treatment step (step 103) is employed on the surface of the medium layer 200, wherein the process of the surface treatment step 103 may be similar to the surface treatment step 101, thereby cleaning the surface of the medium layer 200 and making it easier to form the plating layer 300.
Referring to Table 1, Table 1 shows the relationship between the material of the plating layer and the thickness thereof. After the surface treatment step 103, next, the plating layer 300 is electroplated on the surface of the medium layer 200 (step 104), wherein at least one electroplating process may be employed to form the plating layer 300. According to Table 1, the material of the plating layer 300 may be aurum, copper, zinc, nickel or chromium, and the thickness thereof is substantially between 0.5 μm and 30 μm.

	TABLE 1

	Material of plating layer	Thickness of plating layer (μm)

	aurum	0.1~0.5
	copper	0.5~20
	zinc	0.5~25
	nickel	0.5~30
	chromium	0.3~1

The electroplating method of forming the plating layer 300 may be metal electroplating or electroless plating. Since the material of the medium layer 200 is electroplating-compatible with the material of the plating layer 300, the plating layer 300 can be formed on the surface of the medium layer 200 firmly, thereby enhancing corrosion-resistance, rust-resistance or appearance of the golf club head 100. For example, when the plating layer 300 is a Cr plating layer and formed by the method of metal electroplating or electroless plating, first, an Ni plating layer may be formed on the medium layer 200 to improve adhesion, next, a chromate conversion coating step makes it easier to form the plating layer 300 on the medium layer 200, thereby achieving the plating layer 300 thereon. At this time, the plating layer 300 (Ni or Cr) is very electroplating-compatible with the medium layer 200, and the medium layer 200 is formed on the surface of the golf club head 100, particularly on the surface unable to be electroplating-compatible with the plating layer 300. Therefore, the plating layer 300 is allowed to be electroplated on the surface of the golf club head 100 by the medium layer 200, thereby improving the surface characteristic (such as corrosion-resistance, rust-resistance or appearance) of the golf club head 100, even if the golf club head 100 has the material (such as Ti or Al) that cannot be electroplating-compatible with the plating layer 300.

TABLE 2

	Thickness of	Thickness of	Thickness	Sand blast	High speed
	medium layer	Ni plating	of Cr plating layer	test	ball impact
Item	(μm)	layer (μm)	(μm)	(5 kg/cm2)	test (50 m/s)

1	0.2	0.9	0.4	Fail	Fail
2	0.2	1	0.5	Fail	Fail
3	0.2	20	0.8	Fail	Fail
4	0.2	30	1	Fail	Fail
5	0.3	0.9	0.4	Pass	Fail
6	0.3	0.9	0.5	Pass	Fail
7	0.3	1	0.4	Pass	Fail
8	0.3	1	0.5	Pass	Pass
9	0.3	20	0.8	Pass	Pass
10	0.6	1	0.4	Pass	Fail
11	0.6	5	0.5	Pass	Pass
12	0.6	10	0.5	Pass	Pass
13	0.6	15	0.8	Pass	Pass
14	0.6	20	1	Pass	Pass
15	1.0	0.9	0.5	Pass	Fail
16	1.0	1	0.5	Pass	Pass
17	1.0	20	0.8	Pass	Pass
18	1.0	30	1	Pass	Pass
19	1.0	30	1.1	Fail	Fail
20	1.2	0.9	0.5	Pass	Fail
21	1.2	1	0.5	Pass	Pass
22	1.2	30	1	Pass	Pass
23	1.2	30	1.1	Fail	Fail
24	1.2	30	1.2	Fail	Fail

Referring to Table 2, Table 2 shows a test result about a golf club head with a Ni plating layer and a Cr plating layer. In Table 2, a sand blast test and a high-speed ball impact test are employed to the golf club head 100 with the medium layer 200 and the plating layer 300 (Ni and Cr plating layer) to test the functionality and endurance thereof. According to Table 2, the plating layer 300 is formed on the golf club head 100 firmly by the medium layer 200, thereby enhancing the surface characteristic of the golf club head 100.
It is worth mentioning that the plating layer 300 is at least formed on the surface of the medium layer 200, and a portion of the plating layer 300 may be formed straight on the surface of the golf club head 100. For example, when the material of the main body 110 is stainless steel, and the material of the striking plate 120 is titanium alloy, the medium layer 200 is at least formed on the entire surface of the striking plate 120. At this time, since the plating layer 300 is electroplating-compatible with the main body 110 (stainless steel), portion of the plating layer 300 can be formed on the main body 110.
Therefore, the plating layer structure of this embodiment uses the medium layer 200 formed between the golf club head 100 and the plating layer 300 to enhance the adhesion of the plating layer 300 on the golf club head 100, thereby allowing the plating layer 300 to be electroplated thereon and enhance the surface characteristics thereof.
Refer to FIG. 4. FIG. 4 is a cross-sectional diagram showing a golf club head according to a second embodiment of the present invention. Some reference numerals shown in the first embodiment are used in the second embodiment of the present invention. The construction of the golf club head shown in the second embodiment is similar to that in the first embodiment with respect to configuration and function, and thus is not stated in detail herein.
Refer again to FIG. 4, in comparison with the first embodiment, the golf club head 100 a of the second embodiment may be a Ti-type golf club head, i.e. the main body 110 and the striking plate 120 are made of titanium or a titanium alloy. At this time, the medium layer 200 a may be formed on the whole surface of the golf club head 100a to allow the plating layer 300 to be electroplated on the surface of the golf club head 100 a, thereby enhancing the surface characteristic thereof. Furthermore, the golf club head 100 a may include a cavity 130 a, thereby forming a hollow head. The cavity 130 a may further extend to the bottom of the golf club head 100 a to form an under-cut structure for adjusting the center-of-gravity position thereof.
Refer to FIG. 5. FIG. 5 is a cross-sectional diagram showing a golf club head according to a third embodiment of the present invention. Some reference numerals shown in the first embodiment are used in the third embodiment of the present invention. The construction of the golf club head shown in the third embodiment is similar to that in the first embodiment with respect to configuration and function, and thus is not stated in detail herein.
Refer again to FIG. 5, in comparison with the first embodiment, the golf club head 100 of the third embodiment further comprises a chamber 130 b, a cover plate 140 and a weight member 150, wherein the golf club head 100 may be a hollow head. The chamber 130 b is formed behind the main body 110, and preferably corresponds to the sweet spot of the striking plate 120. The cover plate 140 is disposed behind the main body 110 by the method of inserting, press bonding, brazing, welding, adhesion or screwing. The weight member 150 may be disposed under the main body 110 to change the center-of-gravity position of the golf club head 100. At this time, the cover plate 140 or the weight member 150 may be unable to be electroplating-compatible with the plating layer 300, and the medium layer 200 b can be formed on the surface of the cover plate 140 or the weight member 150 to allow the plating layer 300 to be electroplated thereon.
Therefore, the plating layer structure of the golf club head and the forming method thereof shown in the respective embodiments of the present invention can be electroplated on the golf club head to enhance the surface characteristic (such as corrosion-resistance, rust-resistance or appearance) thereof.
As is understood by a person skilled in the art, the foregoing embodiments of the present invention are strengths of the present invention rather than limiting of the present invention. It is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structure.

Claims

1. A plating layer structure of a golf club head, comprising:

a medium layer formed on the surface of the golf club head; and

a plating layer formed on the medium layer, wherein at least portion of the material of the golf club head is not electroplating-compatible with the material of the plating layer, and the material of the plating layer is electroplating-compatible with the material of the medium layer.

2. The plating layer structure of the golf club head as claimed in claim 1, wherein the golf club head comprises:

a main body, wherein the material of the main body is selected from a group consisting of carbon steel, stainless steel, alloy steel, Fe—Mn—Al alloy, Ni-based alloy, cast iron, titanium alloy, aluminum alloy, Al—Mg alloy, tungsten alloy, copper alloy, ceramics, carbon fiber, plastics or any composition thereof; and

a striking plate disposed on the front side of the main body, wherein the material of the striking plate is selected from a group consisting of carbon steel, stainless steel, Fe—Mn—Al alloy, titanium alloy, aluminum alloy, copper alloy, ceramics, carbon fiber, plastics and any composition thereof.

3. The plating layer structure of the golf club head as claimed in claim 2, wherein the medium layer is formed on the surface of the main body.

4. The plating layer structure of the golf club head as claimed in claim 2, wherein the medium layer is formed on the surface of the striking plate.

5. The plating layer structure of the golf club head as claimed in claim 1, wherein the medium layer is formed by the method of physical vapor deposition (PVD), wherein the physical vapor deposition (PVD) method is evaporation deposition, ion plating or sputtering deposition.

6. The plating layer structure of the golf club head as claimed in claim 1, wherein the material of the medium layer is stainless steel or aluminum.

7. The plating layer structure of the golf club head as claimed in claim 1, wherein the thickness of the medium layer is substantially between 0.3 μm and 1.2 μm.

8. The plating layer structure of the golf club head as claimed in claim 1, wherein the material of the plating layer is nickel or chromium.

9. The plating layer structure of the golf club head as claimed in claim 1, wherein the thickness of the plating layer is substantially between 0.5 μm and 30 μm.

10. A method for forming a plating layer structure of a golf club head, comprising:

forming a medium layer on the surface of the golf club head; and

electroplating a plating layer on the medium layer, wherein at least portion of the material of the golf club head is not electroplating-compatible with the material of the plating layer, and the material of the plating layer is electroplating-compatible with the material of the medium layer.

11. The method for forming a plating layer structure of a golf club head as claimed in claim 10, further comprising:

before forming the medium layer, surface treating the surface of the golf club head.

12. The method for forming a plating layer structure of a golf club head as claimed in claim 10, further comprising:

before forming the plating layer, surface treating the surface of the medium layer.

13. The method for forming a plating layer structure of a golf club head as claimed in claim 11, wherein the plating layer is formed by the method of metal electroplating or electroless-plating.

14. The method for forming a plating layer structure of a golf club head as claimed in claim 11, wherein the medium layer is formed by the method of physical vapor deposition (PVD), wherein the physical vapor deposition (PVD) method is evaporation deposition, ion plating or sputtering deposition.

15. A golf club head, comprising:

a main body including a toe portion, a heel portion and a hosel, wherein the toe portion and the heel portion are respectively located at both ends of the main body, and the hosel extends out one side of the main body and is close to the heel portion;

a striking plate disposed on the front side of the main body;

a medium layer formed on at least one portion surface of the golf club head; and

a plating layer formed on the medium layer, wherein the least one portion surface of the golf club head is not electroplating-compatible with the material of the plating layer, and the material of the plating layer is electroplating-compatible with the material of the medium layer.

16. The golf club head as claimed in claim 15, wherein the least one portion surface of the golf club head is formed on the main body.

17. The golf club head as claimed in claim 15, wherein the least one portion surface of the golf club head is formed on the striking plate.

18. The golf club head as claimed in claim 15, wherein the material of the main body is selected from a group consisting of carbon steel, stainless steel, alloy steel, Fe—Mn—Al alloy, Ni-based alloy, cast iron, titanium alloy, aluminum alloy, Al—Mg alloy, tungsten alloy, copper alloy, ceramics, carbon fiber, plastics or any composition thereof.

19. The golf club head as claimed in claim 15, wherein the material of the striking plate is selected from a group consisting of carbon steel, stainless steel, Fe—Mn—Al alloy, titanium alloy, aluminum alloy, copper alloy, ceramics, carbon fiber, plastics or any composition thereof.

20. The golf club head as claimed in claim 15, wherein the medium layer is formed by the method of physical vapor deposition (PVD), wherein the physical vapor deposition (PVD) method is evaporation deposition, ion plating or sputtering deposition.