Abstract:
A hollow club head having an aluminum alloy base material covered with another material layer of Ni or Ni/P with ceramic granules. The thickness of the material layer on the striking face is thicker than on the rest of the club head. The material layer has a hardness between Hv500 ad Hv850 or greater than Hv1500 and an average granule diameter smaller than 10 microns.

Description:
FIELD OF THE INVENTION 
   The present invention relates to a golf club; more particularly, relates to providing a club head having better endurance and practicality with big size and volume, big areas of strike plate and sweet spot, high coefficient of restitution and coefficient of energy transformation, good hardness and wear resistance, and big friction resistance at the strike plate to avoid side spinning and back spinning. 
   DESCRIPTION OF THE RELATED ARTS 
   Modern golf clubs include woods, iron woods, irons and putters. The woods are also called metal woods made of steel, titanium or glass fiber, etc. 
   A common refinement of metal wood is to obtain a metal wood of titanium alloy with light weight but high strength because a modern metal wood is usually made of titanium alloy. 
   The size of a metal wood used as a first tee shot is usually measured by its volume. The volume of the club head of the metal wood for the first tee shot is greater than 30 cc (cubic centimeter). Although in the regulations of the United States Golf Association, the biggest volume for a club head used in games is 460 cc; yet, for a club head not used in games, its volume may even as big as 600 cc because a club head with big size and big volume contains big sweet spot and high inertia with bigger strike-miss tolerance. 
   Generally, a club head with big size and big volume is thinner in the crown section and the bottom section yet thicker in the heel section and the toe section while having the center of gravity properly adjusted. When striking a ball by a gulf club having this kind of club head, even the striking is not at the center of the strike plate, the flying of the ball will not twist; the spinning of the ball is reduced; the coefficient of restitution of the ball is increased; and the flying distance is increased as well. 
   Yet, a modern club head of titanium alloy has the following disadvantages: (1) The titanium is expensive and must be melted, cast and welded in a vacuum environment. (2) The manufacturing machine and the manufacturing cost are expensive. (3) For manufacturing a hollowed club head with big size, its wall width must be reduced, which may obtain a club head with uneven wall width and other defects and may require complex procedures together with a lot of human resource, material, and time to mend those problems and defects. 
   In the other hand, a club head of aluminum alloy has a density of 2.7 g/cc (gram per cubic centimeter), while a club head of titanium alloy has a density of 4.5 g/cc. It is clear that the density of aluminum alloy is only 60 percents to that of titanium alloy. In order to obtain the flexibility for striking, the weight of the club head must be controlled in a limited range. A heavier club head has a greater inertia and the ball can fly farer after striking. Owing to the lower density of aluminum alloy, under the same weight, the club head can obtain a bigger volume; in another word, a club head can be made of aluminum alloy to obtain a bigger size and volume to increase the sweet spot at the strike plate. And, a club head of aluminum alloy can be made by forging, atmospheric die-casting, vacuum casting or gravity casting, which has the advantage of a relatively lower cost. In order to increase the hardness of the club head of aluminum alloy, it is usually processed with a T6 precipitate hardening process or a surface-hardening anode process so that it will not be over-deformed after striking and waste some striking energy But, the strike plate on the club head of aluminum alloy processed with precipitate hardening and surface-hardening anode process is still not hard enough; the hard layer is not thick enough; and, the durability of the club head is not good enough, etc. So, the prior arts do not fulfill users&#39; requests on actual use. 
   SUMMARY OF THE INVENTION 
   Therefore, the main purpose of the present invention is to obtain a club head with big size and volume together with big areas of strike plate and sweet spot, which has high coefficient of restitution and coefficient of energy transformation, good hardness and wear resistance, and big friction resistance at the strike plate to avoid side spinning and back spinning that better endurance and practicality are achieved while the ball fly farer and its flight trajectory is stabler. 
   To achieve the above purpose, the present invention is a golf club head with a ceramic layer; the club head has a strike plate for striking and comprises a hosel to integrate with a shaft; the club head is made of a base material covered with a hard material layer having higher hardness; the base material is an aluminum alloy and the hard material layer is made of a compound material of Ni with hard ceramic granules or NI/P with hard ceramic granules; and, the hard material layer at the strike plate is thicker than the other parts. Accordingly, a novel golf club head with a ceramic layer is obtained. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will be better understood from the following detailed descriptions of the preferred embodiments according to the present invention, taken in conjunction with the accompanying drawings, in which 
       FIG. 1  is a perspective view of a preferred embodiment according to the present invention; 
       FIG. 2  is a front view of the preferred embodiment according to the present invention; 
       FIG. 3  is an A-A cross-sectional view of  FIG. 2  according to the preferred embodiment of the present invention; 
       FIG. 4  is a view showing a hard material layer at a strike plate of the preferred embodiment according to the present invention; 
       FIG. 5  is a view showing a status of electroplating according to the preferred embodiment of the present invention; 
       FIG. 6  is a view showing a rugged surface of the hard material layer at the strike plate according to the preferred embodiment of the present invention; and 
       FIG. 7  is a view showing a status of use of the preferred embodiment according to the present invention; 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   The following descriptions of the preferred embodiments are provided to understand the features and the structures of the present invention. 
   Please refer to  FIG. 1  through  FIG. 3 , which are a perspective view, a front view, and an A-A cross-sectional view of  FIG. 1 , according to a preferred embodiment of the present invention. As shown in the figures, the present invention is a golf club head with a ceramic layer, whose golf club comprises a shaft  1  and a club head  2 . The club head  2  comprises a hosel  21 , a crown section  22 , a toe section  23 , a bottom section  24 , a hollow interior  25  and a strike plate  26 . The club head  2  is made of a base material covered with a hard material layer  27 . The base material is an aluminum alloy; the hard material layer  27  is made of a compound material of Ni with hard ceramic granules or Ni/P with hard ceramic granules; and, the strike plate  26  has a thicker hard material layer  261 . 
   Therein, the base material of the club head  2  is an aluminum alloy, especially which can be processed with a T6 precipitate hardening process. The aluminum alloy is obtained through forging, atmospheric die-casting, vacuum casting or gravity casting. The shape of the base material of the club is obtained through lathing, milling or grinding; and, afterward, the base material is processed with an manufacturing process—a typical electroplating process for aluminum alloy, including degreasing, micro-etching, acid washing, zinc metathesis and electroplating. 
   And, the hard material layer  27 , 261  is made of Ni with hard ceramic granules or Ni/P with hard ceramic granules, which is obtained through precipitating Ni and/or P together with hard ceramic granules on the surface of the aluminum-alloy-based material under proper conditions. The hard material layer  27 , 261  obtained has a soft part and a hard part, where the soft part is Ni and the hard part is Ni—P together with hard ceramic granules. 
   The hard ceramic granule, such as silicon carbide, boron nitride, tungsten carbide, aluminum oxide, titanium diboride and zirconium borites, has a hardness greater than Hv1500 and has an average granule diameter smaller than 10 micron (μm). The hard material layer obtained has a hardness of Hv500 (Vickers hardness) to Hv800, more preferably Hv600 to Hv750; and, after being further processed with a thermal treatment, the surface of the hard material layer has a hardness of Hv500 to Hv1000, more preferably Hv700 to Hv900. 
   The thickness of the hard material layer  27 , 261  can be changed according to various applications. The thickness of the hard material layer  261  at the strike plate  26  is thicker than that of the hard material layer  27  at the other parts of the club head to obtain higher coefficient of restitution. So, the hardness and the thickness at the strike plate is in creased with a thickness of the hard material layer  261  at the strike plate as 30 μm to 500 μm, more preferably, 50 μm to 250 μm, while a thickness at the other parts is 100 μm to 100 μm, more preferably, 20 μm to 30 μm. Various thicknesses at various parts of the hard material layer  27 , 261  are obtained through changing a node shape, and/or shielding, covering and pasting. Hence, a novel golf club head with a ceramic layer is obtained. 
   Please refer to  FIG. 4 , which is a view showing the hard material layer at the strike plate of the preferred embodiment according to the present invention. As shown in the figure, in order to increase the coefficient of restitution at the strike plate, scorelines  262  (in  FIG. 2 ) at the strike plate  26  can be made before being processed with electroplating. In order to increase the stability in the flight trajectory of the gulf ball after striking, the area of the strike plate  24  and the size and the volume of the club head  2  are usually increased with the center of gravity properly adjusted to prevent back spinning. 
   Owing to the limitation over the weight of the club head  2  on designing, which is 200 g (gram) to 300 g, a metal wood is hollowed to increase the area of the sweet spot and the stability of the gulf ball after striking. Because the aluminum alloy has a density lower than that of a traditional titanium alloy, a hollow shape can obtain bigger size and volume while distributing more weight of the club head  2  to the toe section  23  and the heel section  28  (in  FIG. 2 ). Hence, a secure hardness for striking can be obtained with the thick plane section; and, so, the sweet spot is increased in area and a better stability in the flight trajectory of the gulf ball is obtained as well. 
   Please refer to  FIG. 5  and  FIG. 6 , which are views showing a status of electroplating and showing a rugged surface of the hard material layer at the strike plate according to the preferred embodiment of the present invention. As shown in the figures, when electroplating, the club head  2  is connected to a cathode  31  of a power supplier  3 ; a soluble nickel anode  32 , such as a nickel ball, a nickel slice, a nickel plate or a nickel strip, is connected to an anode  33  of the power supplier  3 ; and, an nickel sulphate or nickel sulphamate is obtained as an electroplating liquid  35  in an electroplating trough  34 , where the electroplating liquid  35  is added with hard ceramic granules. After properly adjusting the components of the electroplating liquid  35  and the time and the current for the electroplating, a hard material layer  27  is obtained in the end with a consistency of phosphorus in 0.5 wt % to 10 wt %, more preferably 0.6 wt % to 3 wt % and with a consistency of hard ceramic granule in 1 wt % to 10 wt %, more preferably 2 wt % to 4 wt %. And, by properly adjusting the conditions for electroplating, a more rugged surface of the hard material layer  261  is obtained so that the friction resistance is increased and the side spinning and the back spinning can be avoided on striking. 
   Please refer to  FIG. 7 , which a view showing a status of use of the preferred embodiment according to the present invention. As shown in the figure, when striking a gulf ball  4  with a gulf club having the club head  2  according to the present invention, the strike plate  26  is slightly concaved; yet, owing to the high hardness on the surface layer of the strike plate  26 , a strong rebound is obtain with the high coefficient of restitution. And, owing to the strong rebound caused by the slight concave of the strike plate  26 , the gulf ball  4  can fly a farer distance; in addition, for the friction resistance is increased, the side spinning and the back spinning of the gulf ball  4  after being struck out are reduced to stabilize the flight trajectory of the ball. 
   To sum up, the present invention is a golf club head with a ceramic layer, which has advantages of a bigger golf club head in size and volume, bigger areas of a strike plate and a sweet spot, high coefficient of restitution and high coefficient of energy transformation; and which obtains better endurance and practicality with hard material layer of good hardness and good wear resistance and with the strike plate having good friction resistance to avoid side spinning and back spinning for a more stable flight trajectory. 
   The preferred embodiments herein disclosed are not intended to unnecessarily limit the scope of the invention. Therefore, simple modifications or variations belonging to the equivalent of the scope of the claims and the instructions disclosed herein for a patent are all within the scope of the present invention.