Metal fusion bonding – Process – Preplacing solid filler
Reexamination Certificate
1999-09-13
2001-04-03
Evans, Geoffrey S. (Department: 1725)
Metal fusion bonding
Process
Preplacing solid filler
C228S262300, C228S262410, C228S262710
Reexamination Certificate
active
06209777
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a fusion welding method for binding the surfaces of two metals, and particularly to a fusion welding method by applying a powdery medium on the metal binding surfaces so as to form eutectics at same surfaces upon sintering the surfaces in vacuum, thereby fusing and welding the binding surfaces of the two metals together.
2. Description of Prior Art
Conventionally, “welding” process carried out at a higher temperature has normally been adopted for binding two metals so as to obtain a higher binding strength as compared with the case of “soldering” process carried out at a temperature below 450° C. by employing lower melting point solder such as tin or lead. Instead of lower melting point solder used in “soldering”, brazing solder of higher melting point, mainly composed of noble metals containing gold, silver, copper, nickel, etc, is usually used in “welding” process. Brazing solder composed of the above noble metals mixed by certain ratio will form eutectics, thus lowering the melting point of the brazing solder, which is normally in the range of about 600° C. to 1100° C. that may be selected depending on welding condition.
For instance, in the fabrication of the head portion of the golf club, the bottom of the head portion needs to be bound with a weight of a higher specific gravity so as to lower the center of gravity of the head portion. As a result, an initial swing of the club can hit the ball to a further distance. In addition, the hitting plate of the head portion should be made of composite materials formed through special metal processing or heat treatment so as to obtain high strength and high coefficient of elasticity. Thus, the hitting plate may withstand impact and may produce a light sound upon hitting the ball.
FIG. 1
shows a schematic view illustrating the binding of a weight to the head portion of the golf club by a conventional welding method. First, provide a recess
111
in the bottom surface
11
of the head portion. Then, coat a layer of brazing solder
12
on the bottom surface of the recess
111
, and press a weight
13
to fit into the recess
111
over the layer of brazing solder
12
. Subsequently, the entire structure is placed into a vacuum furnace for sintering at a temperature slightly higher than the eutectic point of the brazing solder
12
. Through such a sintering process in vacuum, the brazing solder
12
melts first, and then, under high temperature, the melt brazing solder
12
penetrates into the bottom surface
11
and the weight
13
due to capillary penetration, so as to bind the bottom surface
11
and the weight
13
together.
Though the above conventional welding method is superior to soldering method in its obtainable binding strength, it suffers from the below drawbacks:
1. Expensive brazing solder composed of noble metals;
2. Relatively higher binding cost;
3. Necessity of pressing the two metals to be bound against each other;
4. Restriction to the thickness of the coated brazing solder;
5. Necessity of relatively precise control in welding process for obtaining better binding effect; and
6. Poor welding effect if the metal to be bound has a density larger than 14 g/cm
3
because, in this case, capillary penetration becomes poor.
FIG. 2
shows another conventional way of attaching a weight to the head portion of the golf club. A weight
13
is screw fastened to the bottom surface
11
of the head portion by a plurality of (only one is shown in
FIG. 2
) screws
14
made of titanium for improving the rust protection effect and obtaining higher fastening strength at the fastened portion. Each screw
14
penetrates through a through hole
131
provided in the weight
13
and then threaded into a screw hole
112
provided in the bottom surface
11
corresponding to a through hole
131
. After that, the heads of the screws
14
are polished to provide an overall aesthetic appearance.
This conventional method of screw fastening two metals has the drawbacks as follows:
1. The cost of fabrication is high because titanium screw is expensive and a polishing step must be employed.
2. In the state wherein the weight
13
is screw fastened to the bottom surface
11
, a gap is always remained between the weight
13
and the recess
111
. This gap differs from one golf club to another due to the fabrication precision of the weight
13
and the recess
111
, or due to difference in the applied force for tightening the screws
14
. The unevenness in the gap between the weight
13
and the recess
111
of the bottom surface
11
will cause difference in the sound produced when the head portion of the golf club hits a ball, thus resulting in unevenness in the quality of the golf club. Consequently, its is difficult to control the quality of the produced golf club by use of this conventional method.
SUMMARY OF THE INVENTION
Accordingly, one object of the present invention is to provide a fusion welding method for metal binding surfaces, wherein the metal binding surfaces per se are melted as a result of eutectic phenomenon so as to provide a binding effect.
Another object of the present invention is to provide a method of binding a weight to the head portion of a golf club, wherein the metal binding surfaces per se are melted as a result of eutectic phenomenon so as to provide a high binding strength. This is a simple method of binding the weight to the head portion, and at the same time, the cost of production is lowered.
Another object of the present invention is to provide a method of binding the hitting plate of the head portion of the golf club, wherein the metal binding surfaces per se are melted as a result of eutectic phenomenon so as to provide a high binding strength. This is a simple method of binding the hitting plate to the head portion, and at the same time, the cost of production is lowered.
For achieving the above objects, a fusion welding method for binding the surfaces of two metals according to the present invention comprises the steps of (a) selecting a first metal member from one of Ni—Fe—W alloy and stainless steel; (b) selecting a second metal member from one of Ni—Fe—W alloy and stainless steel; (c) applying Carbon powder onto a binding surface of at least one of the two metal members, the Carbon powder capable of forming a fusion region with the two metal members at an eutectic temperature; (d) heating the two metal members with the Carbon powder in a vacuum furnace at a sintering temperature higher than the eutectic temperature of the fusion region and lower than the melting temperatures of the two metal members.
REFERENCES:
patent: 3716347 (1973-02-01), Bergstrom et al.
patent: 4228944 (1980-10-01), Inamura et al.
patent: 4289833 (1981-09-01), Hachisuka
patent: 4300951 (1981-11-01), Hachisuka
patent: 4591480 (1986-05-01), Morishita et al.
patent: 5154425 (1992-10-01), Niskanen et al.
patent: 5356453 (1994-10-01), Takata
patent: 5812925 (1998-09-01), Ecer
patent: 408238340 (1976-09-01), None
patent: 357022867 (1982-02-01), None
patent: 409024122 (1997-01-01), None
patent: 410146404 (1998-06-01), None
Chuang Tien-tzu
Tung Chao-nien
Bacon & Thomas
Evans Geoffrey S.
New Century Technology Co., Ltd.
Stoner Kiley
LandOfFree
Fusion welding method for binding surfaces of two metals does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Fusion welding method for binding surfaces of two metals, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fusion welding method for binding surfaces of two metals will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2522826