JP3009081B2 - Lightweight superabrasive metal bond wheel and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a super-abrasive metal bond wheel used for various grinding operations such as a straight type, a cup type and a double-headed grinding wheel, and more particularly to a super-abrasive metal bond using an aluminum alloy as a base metal. About the wheel.

[0002]

2. Description of the Related Art Conventionally, a superabrasive metal bond wheel in which a superabrasive layer is fixed to a base metal has been used for various kinds of grinding of carbide, ceramics, glass or tool steel.

In such a metal bond wheel, an iron base metal excellent in strength is generally used, and a superabrasive layer is fixed to the outer periphery and side surfaces of the base metal.

[0004] However, such an iron base metal is excellent in strength, but has a heavy weight. Therefore, with a grinding machine having a low spindle rigidity, the spindle oscillates during wheel rotation, and stable grinding cannot be performed. There is a problem that work is difficult. In addition, since the wheel mounting holes and the reference surface are rusted by the grinding fluid or moisture, there is another problem that accurate mounting cannot be performed and high-precision grinding cannot be performed.

[0005] In order to solve such disadvantages, a lightweight superabrasive metal bond wheel made of an aluminum alloy has recently been developed. According to such a base metal, the weight of the wheel is reduced to about one third of that of iron, so that the weight can be significantly reduced, and stable grinding can be performed even with a grinding machine having a low spindle rigidity.

As a method of manufacturing a metal bond wheel made of such an aluminum alloy base metal, a superabrasive layer is fixed to a conventional iron base metal by a direct bonding method, and after sintering, an inner peripheral portion of the base metal is hollowed out. Alternatively, a method of bonding an aluminum alloy base metal with an adhesive or sintering a superabrasive layer in a ring shape in advance and applying the adhesive to an aluminum alloy base metal There is known a method of bonding by using the same.

[0007]

However, in the former method, the outer periphery occupying most of the wheel weight is made of iron, so that not only a sufficient weight reduction cannot be achieved but also the manufacturing process becomes complicated. In addition, the adhesive at the time of grinding causes deterioration of the adhesive, and there is also a problem in the adhesive strength. In the latter method, the ring of the superabrasive layer is deformed due to thermal shrinkage during sintering, so it is necessary to process the aluminum alloy base according to the deformation, which complicates the manufacturing process, Requires a high level of bonding technology, and there remains a problem in bonding strength.

Therefore, an object of the present invention is to solve the above-mentioned conventional problems, and a super-abrasive metal bond wheel having a strong super-abrasive layer and a superior lightweight is provided. An object of the present invention is to provide a means for efficiently manufacturing a superabrasive metal bond wheel.

[0009]

In order to solve the above-mentioned problems, the present invention comprises a base metal and a superabrasive layer fixed to the base metal, wherein the base metal is made of an aluminum alloy, and The abrasive layer is fixed by sintering via a metal plating layer having a melting point higher than the sintering temperature of the superabrasive layer formed on the surface of the base metal.

A method for manufacturing a superabrasive metal bond wheel is to form a metal plating layer having a melting point higher than the sintering temperature of the superabrasive layer on the surface of an aluminum alloy base metal, and to place the base metal in a mold. A superabrasive layer material mainly containing superabrasive grains and metal powder is filled so as to be in contact with the plating layer, and then the superabrasive layer material is pressure-formed. ° C
And sintering in a temperature range lower than the melting point of the base metal to form a superabrasive layer and simultaneously fix the superabrasive layer to the base.

Here, if the linear expansion coefficient between the aluminum alloy and the superabrasive layer is large, the superabrasive layer may be cracked or peeled off.
21 × 10 ^-6 / ° C from the same or higher than the linear expansion coefficient of the superabrasive layer
It is desirable to be within the following range. Since the linear expansion coefficient of the raw material of the superabrasive layer varies depending on the type of metal bond, the superabrasive content (concentration) and the amount of the additive (filler), use an aluminum alloy with a linear expansion coefficient corresponding to that. I do. The linear expansion coefficient of the base metal can be adjusted by using, for example, an aluminum alloy containing a large amount of silicon.

The metal plating formed on the surface of the base metal includes:
What was formed by the conventional electrolytic plating can be used, and nickel plating or copper plating excellent in adhesion to an aluminum wheel is desirable.

As the metal bond that can be sintered at a temperature lower than the melting point of the aluminum alloy, a bronze-based metal bond having a high tin ratio, whose main component is copper and tin, can be used.

The manufacture of a wheel using the above materials can be performed by a conventional hot pressing method. At this time, the pressure is preferably 25 MPa or more in order to obtain adhesion between the metal plating on the surface of the base metal and the raw material of the superabrasive layer.

[0015]

In the superabrasive metal bond wheel of the present invention, the superabrasive layer material is solidified by the high temperature during sintering, and the metal plating layer on the surface of the aluminum alloy base metal is combined with the superabrasive layer. And the formed superabrasive layer is fixed to the aluminum alloy.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 (a) is a view showing a working process of the present invention.
First, a metal plating layer is formed on the surface of the aluminum alloy base metal 1 by a conventional method. Next, the lower press die 2 and the outer die 3 are arranged below and around the base metal 1. And the base 1
The space formed by the lower die 2 and the outer die 3 is filled with a superabrasive layer material. Further, the raw material of the superabrasive layer is pressed from above by the upper pressing die 5, and then sintered by hot pressing. As a result, the superabrasive layer 4 is fixed to the outer periphery of the base metal 1. Thereafter, the inclined portion 6 is cut in accordance with the width of the superabrasive layer 4, and the superabrasive metal bond wheel 7 shown in FIG.
Is completed.

FIG. 2 is a partial plan view of the superabrasive metal bond wheel 7, wherein 1 is a base metal, 8 is a plating layer on the outer periphery of the base metal 1, and 4 is a superabrasive layer. In the embodiments of FIGS. 1 and 2, a so-called straight type wheel has been described. However, the present invention is not limited to this, and it is needless to say that the present invention can be applied to a cup type, double-head grinding wheel, and the like. .

[Test Example] As an example, an aluminum alloy casting AC8 having a linear expansion coefficient of 19 × 10 ⁻⁶ / ° C. was used as a base metal.
A was used to form a copper plating layer of 30 μm on the surface of the base metal. Further, on this outer periphery, a bronze-based metal bond of 65% by weight of copper and 35% by weight of tin and a super-abrasive particle size of
170 (mesh size) synthetic diamond was filled at a content of 25% by volume. This was sintered at a temperature of 500 ° C. and 30 MPa for 2 hours by the above method. After that, cutting is performed, wheel outer diameter 150mm, super abrasive layer thickness 3m
m, superabrasive layer width 5 mm, wheel mounting hole diameter 31.7
A 5 mm superabrasive metal bond wheel was made.

As a comparative example, an abrasive grain layer having the same dimensions and the same composition and previously sintered in a ring shape was fixed to an aluminum alloy base metal via an adhesive.

The two products were mounted on a rotation tester, and the rotation speed was increased until the wheel broke. As a result, the example product did not break even at 21,000 rpm (peripheral speed: 164 m / sec), which is the upper limit of the number of rotations of the machine. On the other hand, in the comparative example, 13,000 rotations (peripheral speed: 102 m /
Seconds), the superabrasive layer came off the base metal and was broken.

Next, a grinding test was actually performed using the product of this embodiment and the product of the comparative example. Wheel dimensions and blending contents are the same as those of the above-mentioned test example products. As for the grinding conditions, a 100 cc grinding test was performed on alumina ceramics at a wheel rotation speed of 2000 rpm (peripheral speed: 16 m / sec) and a cut of 0.02 mm / pass using a 2-horsepower surface grinder.

FIG. 3 shows the chipping (break of the ground surface of the workpiece), the surface roughness (Rmax), the grinding ratio (the amount of workpiece removal / the amount of wheel polishing) and the average power consumption during grinding. The product of this example had a clear advantage.

[0023]

According to the present invention, the following effects can be obtained.

(1) High-precision grinding can be performed even with a grinding machine having a low spindle rigidity due to weight reduction.

(2) Since the metal plating layer and the metal bond are metallically bonded, the aluminum alloy base metal having excellent lightness can be securely bonded to the superabrasive layer, and the bonding strength is high. Excellent safety.

(3) Since the pressure sintering of the abrasive layer and the fixation to the base metal can be performed at the same time, the manufacturing process is simplified and the productivity is good.

(4) Since the pressure sintering of the abrasive layer and the fixing to the base metal can be performed at the same time, the shape of the abrasive layer can be formed into an arbitrary shape.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view for explaining a manufacturing process of the present invention, and FIG. 1B is a cross-sectional view of a superabrasive metal bond wheel manufactured by the present invention.

FIG. 2 is a partial plan view of a superabrasive metal bond wheel manufactured according to the present invention.

FIG. 3 is a diagram showing test results.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aluminum alloy base metal 2 Down-press type 3 Outer mold 4 Super-abrasive layer 5 Top-press type 6 Deleted part 7 Super-abrasive metal bond wheel 8 Metal plating layer

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-52-14289 (JP, A) JP-A-50-139487 (JP, A) JP-A-61-152374 (JP, A) JP-A 57-142 15673 (JP, A) JP-A-64-64779 (JP, A) JP-A-2-15977 (JP, A) JP-A-2-237770 (JP, A) JP-A-3-7463 (JP, U) JP-B-37-747 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) B24D 3/06 B24D 3/00

Claims (3)

(57) [Claims] A superabrasive grain comprising a base metal and a superabrasive layer fixed to the base metal, wherein the base metal is made of an aluminum alloy, and wherein the superabrasive layer is formed on a surface of the base metal. A lightweight superabrasive metal bond wheel which is fixed by sintering via a metal plating layer having a higher melting point than the sintering temperature of the layer. 2. The aluminum alloy base metal has a linear expansion coefficient equal to or more than the linear expansion coefficient of the superabrasive layer, and 21 × 10 ^−6.
The lightweight superabrasive metal bond wheel according to claim 1, wherein the temperature is in the range of / C or lower. 3. A metal plating layer having a melting point higher than the sintering temperature of the superabrasive grain layer is formed on the surface of the aluminum alloy base metal, and this base metal is assembled in a mold so as to contact the plating layer. A superabrasive layer material containing superabrasive grains and metal powder as main components is filled, and then the superabrasive layer material is pressure-formed, and the formed body is 350 ° C. lower than the melting point of the base metal. A method for manufacturing lightweight superabrasive metal bond wheels that sinter in the temperature range.