JPH11333730A - Diamond lapping surface plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently machine hard and brittle materials at high precision by setting the occupied ratio of a machining surface of a diamond layer to the area ratio in relation to all machining surface of a lapping surface plate and the specified range and forming the composition of a binding material from the specified amounts of copper, tin and graphite. SOLUTION: In a diamond layer, diamond abrasive grains are bound by a binding material and fixed to the front surface of a lapping surface plate, the occupied ratio of a machining surface of the diamond layer is set to 40% to 80% of a value of the area ratio in relation to the whole machining surface of the lapping surface plate, and the residue is taken as a chip pocket. The binding material is composed of copper of 33 to 75 wt.%, tin of 18 to 55 wt.% and graphite of 2 to 20 wt.% and formed into bronze. Therefore, various hard and brittle materials can be continuously machined at high machining speeds, high efficiency and high accuracy without dressing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cemented carbide, cermet, altic, glass, sapphire, ceramics, quartz, silicon, ferrite, neodymium magnet,
The present invention relates to a high-performance diamond wrap surface plate capable of processing hard and brittle materials such as samarium cobalt with high precision and efficiency.

[0002]

2. Description of the Related Art As an example of a conventional processing technique of a diamond-wrapped surface of a hard and brittle material, plane processing of a cemented carbide will be described. We will discuss processing. recent years,
Extremely high-precision cutting and grooving with high efficiency due to rapid technological innovation such as ultra-precision processing of ferrite, silicon, samarium cobalt, neodymium magnet, sendust, alnico magnet, glass, ceramics, crystal, etc. Is required to do so. In order to cut the above various materials, diamond, superabrasive cutting wheel using superabrasive such as CBN, superabrasive band saw,
Super-abrasive inner peripheral blades are used depending on the purpose, but among these super-abrasive tools, in particular, super-abrasive cutting wheels are used for a very wide range of applications because they have extremely good machining efficiency and are easy to use. ing.

[0003] Super abrasive cutting wheels are made of steel, molybdenum,
Super abrasive grains are fixed to the outer peripheral edge of a disk-shaped substrate made of a material such as tungsten by a bonding material such as a resin bond, a metal bond, a vitrified bond, and an electrodeposition bond. As the material of the substrate, steel that is easy to carry out precision processing and is easily available at a low price is most often used.However, when processing with a high material removal rate, that is, high efficiency cutting processing, a large cutting stress is applied to the substrate. Since this deforms the substrate, the superabrasive cutting wheel meanders, shoots to cause a significant decrease in cutting accuracy, and causes chipping.

In order to solve this problem and to cope with high-efficiency processing and high-precision processing, a superabrasive cutting wheel using a hard metal on a disk-shaped substrate has been developed. Cemented carbide is
Compared with steel, the elastic modulus is large, so the amount of deformation with respect to cutting stress is small, and the thermal expansion coefficient is small, so that the amount of deformation with respect to heat generated during cutting is small, and the substrate material for superabrasive cutting wheels Has excellent physical properties. However, in a manufacturing process of a superabrasive cutting wheel, it takes time and is troublesome to use a diamond tool to process a cemented carbide substrate to a thickness accuracy and a plane accuracy of a product standard.

More specifically, a super-abrasive cutting wheel for a cemented carbide substrate mainly uses an alloy powder of copper, tin, nickel, cobalt, iron or the like on the outer periphery of a precision-finished cemented carbide substrate. Metal bond as a component, resin bond as a main component of thermosetting resin, vitrified bond as a main component of inorganic material such as glass, electroplating, electrodeposition bond with nickel as the main component deposited by chemical plating, etc. Super abrasive grains are fixed by a binder. Here, to process the thickness, hole diameter and outer diameter of the substrate made of cemented carbide to the dimensional accuracy of the product standard,
A diamond tool such as a diamond wheel is used. Particularly difficult in these processes is the processing of the thickness,
Efficient planar processing that satisfies both specified thickness accuracy and planar accuracy is required.

In order to process the thickness of the substrate made of cemented carbide, a resin-bonded diamond wheel is mounted on a horizontal axis rotary table type surface grinding machine or a vertical axis rotary table type surface grinding machine in order to roughly process the material. Next, for finishing processing, using a grinding machine called a lapping machine, a double-sided lapping machine, a single-sided lapping machine, a parallel plane honing machine, as a diamond tool, diamond abrasive grains are bonded by a bonding material, A diamond wrap surface plate is used in which what is called a disk-shaped pellet is fixed to a wrap surface plate. The most commonly used double-sided lapping machine
A work in which two diamond wrap plates are attached vertically to the rotating shaft of the grinding machine, and a substrate made of cemented carbide, which is a workpiece, is held in a hole on the lower diamond plate. The carrier is meshed with the sun gear and the internal gear, the upper diamond wrap plate is pressed against the lower diamond wrap plate with a certain pressure, and the work carrier is revolved while rotating, so that the upper and lower surfaces of the workpiece are up and down. It is processed with a diamond wrap surface plate. At this time, there is a case in which the upper and lower diamond wrap plates are processed while swinging with a small width in the surface direction, or a single-side lap surface plate in which only the lower diamond wrap plate is processed on one side.

However, the conventional diamond wrap platen in which diamond is bonded by any of resin bond, metal bond, vitrified bond, and electrodeposited bond is not only sharp, but also requires a long processing time.
There has been a serious problem of distortion of the substrate. The excellent wear resistance of the bonding material during dressing means that the bonding material does not easily recede, making dressing work cumbersome and time-consuming, and the need to temporarily suspend machining of the workpiece. Had reduced efficiency. Not only that, even if loose abrasives or conventional grinding stones for dressing are selected according to the specifications of the pellets, the diamonds have a strong tendency to fall off and crush, making it very difficult to obtain good diamond protrusion. However, there was also a problem that the sharpness was not sufficiently recovered. The above-mentioned problems are not limited to the case where the workpiece is made of a cemented carbide substrate of a super-abrasive cutting wheel. In addition to a cemented carbide slitter, a cemented carbide lead wire cutter, a cermet, an Altic (Al ₂₎ O ₃ -Ti
This was almost the same in the case of planar processing of various hard and brittle materials such as C), glass, sapphire, ceramics, quartz, silicon, ferrite, neodymium magnet, and samarium cobalt.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems. In other words, a diamond wrap surface plate that can efficiently process hard and brittle materials such as cemented carbide, cermet, altic, glass, sapphire, ceramics, quartz, silicon, ferrite, neodymium magnets, and samarium cobalt, and can perform plane processing with high precision. Is to provide.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is used by attaching to a grinding machine having a mechanism for holding a workpiece with a work carrier revolving while rotating and performing plane machining. A diamond lapping surface plate in which a diamond layer formed by bonding diamond abrasive grains with a bonding material is fixed to the surface of the lapping surface plate. 40% ~ in area ratio to surface (working surface / total surface)
A diamond wrap set within the range of 80%, wherein the composition of the binder comprises 33 to 75% by weight of copper, 18 to 55% by weight of tin, and 2 to 20% by weight of graphite. It is a surface plate. The workpiece is intended for various hard and brittle materials such as cemented carbide, cermet, altic, glass, sapphire, ceramics, quartz, silicon, ferrite, neodymium magnet, and samarium cobalt. It enables plane processing with high accuracy and almost no need to dress.

The workpiece is a WC-based cemented carbide,
Dimensions are outer diameter Φ10 ~ Φ300mm, thickness 0.01mm
It is intended for a substrate of a super-abrasive cutting wheel of up to 3 mm, and the average grain size of the diamond abrasive grains of the diamond layer is 2
0 to 800 μm, and the concentration is 5 to 100.

Hereinafter, the present invention will be described in detail. The greatest feature of the present invention is the horizontal axis rotary table type surface grinder for various hard and brittle materials such as cemented carbide, cermet, altic, glass, sapphire, ceramics, crystal, silicon, ferrite, neodymium magnet, and samarium cobalt. Alternatively, the grinding speed is faster than that of rough grinding with a diamond wheel mounted on a vertical-axis rotating table type surface grinder, extremely high efficiency, high accuracy, and excellent grinding ability that can continue machining with almost no dressing It is to have.

As a machining method of a grinding machine, a work carrier which meshes with a sun gear and an internal gear and revolves while rotating, holding a workpiece is the most suitable for the grinding performance of the diamond wrap surface plate of the present invention. Withdrawal, roughing and finishing can be performed at the same time, processing can be continued without dressing, and a high-precision plane is obtained.

The diamond layer is formed by bonding diamond abrasive grains with a binder and forming the diamond layer and fixing the diamond layer to the surface of a lap platen. The value of the area ratio (working working surface / total working surface) is 40% to 80%, and the remaining 20% to 60%
% Is a space without a diamond layer, that is, a chip pocket. The reason for limiting the numerical value is that if the occupation ratio of the diamond layer is less than 40%, the amount of diamond abrasive grains acting on the processing is too small, causing a decrease in accuracy due to early wear of the diamond layer. This is not only because the flow of the grinding fluid is hindered and causes clogging, but also because the processing pressure per unit area on the workpiece is too low, leading to a reduction in efficiency. However,
The occupancy is preferably in the range of 50% to 75% and is determined appropriately according to the processing conditions.

The form of the diamond layer is not only what is called a diamond pellet formed into a disk shape or a column shape by mixing diamond abrasive grains and a binder, but also what is formed into a ring shape, an arc shape, and a rod shape. Of these, one or two or more kinds are mixed and fixed to the lap plate, or a diamond layer is fixed to the entire surface of the lap plate and then grooves and recesses are provided on the surface. The method is preferable because the cost required for the production is small and the production is easy.

The composition of the binder is: copper: 33 to 75% by weight;
Tin: 18 to 55% by weight, graphite: 2 to 20% by weight,
Bronze with a high tin composition, its structure is composed mainly of ε phase with high hardness and high Young's modulus, and while having high abrasive grain holding power and high working pressure resistance characteristics, by adding graphite, It gives good truing and dressing properties, and provides extremely good sharpness and sufficient life. Extremely good sustainability of the sharpness is due to the high abrasive holding power and little abrasive drop-off, and the hardness enough to prevent the abrasive from sinking into the binder even at high processing pressures. This is because the bonding material layer has a characteristic of slowly retreating at an appropriate speed due to contact with an object and maintaining effective projection of the abrasive grains. For truing, it is appropriate to use a diamond dress carrier in which diamond abrasive grains are fixed to a work carrier by electrodeposition, etc., because the highest precision flatness is obtained, but a method of grinding a conventional grindstone with a high degree of bonding But it is possible. The dressing has a softer degree of bonding, and can be easily performed, for example, in the same manner as a method of grinding a workpiece with a G or H WA grindstone. At the time of this dressing, it is extremely important not to over-dress the dressing so as not to lower the high-precision flatness obtained by truing. In addition,
When processing efficiency is emphasized, the composition of the binder is copper: 40 to
It is preferable to set the range of 65% by weight, 25 to 50% by weight of tin, and 5 to 18% by weight of graphite.

When a workpiece made of a cemented carbide substrate of a superabrasive cutting wheel is used as a workpiece, an ultrafine WC-based cemented carbide is preferable. For example, WC-Co based cemented carbide, WC-
TaC-NbC-Co cemented carbide, WC-TiC-Ta
C-NbC-Co cemented carbide, WC-TaC-Co cemented carbide, WC-TiC-Co cemented carbide, WC-TiC
It is suitable for processing of -TaC-Co based cemented carbide and the like. The outer diameter is Φ10mm to Φ300, based on the substrate size of the super-abrasive cutting wheel used for ferrite, silicon, samarium cobalt, neodymium magnet, sendust, alnico magnet, glass, ceramics, crystal, etc.
mm and a thickness of 0.01 mm to 3 mm. Among them, the most frequently used one has an outer diameter of Φ50 mm to Φ25.
0 mm and a thickness of 0.05 mm to 2 mm.

The diamond layer has an average particle diameter of diamond abrasive grains of 20 μm to 800 μm and a degree of concentration of 5 to 100, and defines an optimum particle diameter and degree of concentration for planar processing of a cemented carbide substrate. In particular, when processing a cemented carbide substrate of a superabrasive cutting wheel, the most optimal specification may be set within a range of an average particle diameter of diamond abrasive grains of 50 μm to 300 μm and a concentration degree of 15 to 75. High processing accuracy and high processing efficiency.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described in detail in the following Examples.

[0019]

(Example 1) A binder composed of 65% by weight of copper, 32% by weight of tin, and 3% by weight of graphite and diamond abrasive grains (average particle diameter: 100 μm) were mixed so as to have a concentration of 75. Then, a diamond layer was formed in a ring shape and a pellet shape, and these were fixed to a cast iron platen main body by an adhesive or soldering to produce a diamond wrap platen.
The size of the ring-shaped peripheral diamond layer is Φ600-5
w-8t (Φ: outer diameter, w: width, t: thickness, unit: m
m, the same applies hereinafter), the size of the ring-shaped inner peripheral diamond layer is Φ230-5w-8t, and the size of the pellet is Φ1
3-8t. The occupancy of the working surface of the diamond layer was set to 70% in terms of the area ratio (working surface / total working surface) to the entire working surface of the lap platen.

The diamond wrap surface plate is mounted on a double-sided lapping machine having a mechanism for holding a workpiece by a work carrier that revolves while rotating, and is trued with a diamond dress carrier to reduce the flatness of the diamond layer to 3 degrees.
μm or less, after dressing with a GC square whetstone,
WC-Co based cemented carbide substrate with dimensions of outer diameter Φ100
The effect of the present invention was confirmed by processing a material having a thickness of 0.3 mm and a thickness of 0.3 mm and comparing the performance with a conventional diamond wrap plate having pellets fixed on the entire surface. The rotation speed of the diamond wrap platen is 65r. p. m, processing was performed at a processing pressure of 0.5 kgf / cm ^{2 on the} workpiece. In this embodiment, the processing speed was about 4 to 5 times that of the conventional product, and the conventional product required dressing during the processing. However, in the example, the processing could be continued without dressing.

(Example 2) A binder composed of 60% by weight of copper, 35% by weight of tin, and 5% by weight of graphite and diamond abrasive grains (average particle size: 70 μm) were mixed so as to have a concentration of 75. A diamond layer was formed in a ring shape and a pellet shape, and these were fixed to a cast iron platen main body to produce a diamond wrap platen. The size of the ring-shaped outer peripheral diamond layer is Φ600-5w-8t, Φ580-5w-8.
t, the size of the ring-shaped inner peripheral diamond layer is Φ230
-5w-8t, Φ250-5w-8t, and the size of the pellet is Φ13-8t. The occupation ratio of the working surface of the diamond layer was set to 60% in terms of the area ratio to the entire working surface of the lap platen.

This diamond wrap surface plate is mounted on a double-sided lapping machine, truing with a diamond dress carrier, so that the flatness of the diamond layer is 3 μm or less,
After dressing with a GC square grindstone, the dimensions of the WC-Co based cemented carbide substrate were 150 mm in outer diameter and 0.1 mm in thickness.
The effect of the present invention was confirmed by processing a 5 mm piece and comparing the performance with a diamond wrap platen in which a conventional pellet was fixed on the entire surface. The rotation speed of the diamond wrap platen is 70 r. p. m, machining pressure on workpiece is 0.5
When processing was performed at Kgf / cm ^{2, the} processing speed of this embodiment was about six times that of the conventional product, and the conventional product required dressing in the middle of processing. Was able to continue.

Example 3 A binder consisting of 55% by weight of copper, 40% by weight of tin, and 5% by weight of graphite and diamond abrasive grains (average particle size: 100 μm) were mixed so as to have a concentration of 75. Diamond layers were formed in a ring shape and a pellet shape, and these were fixed to a cast iron platen main body by an adhesive or soldering to produce a diamond wrap platen. The size of the ring-shaped outer diamond layer is Φ600
-5w-8t (Φ: outer diameter, w: width, t: thickness, unit: m
m, the same applies hereinafter), the size of the ring-shaped inner peripheral diamond layer is Φ230-5w-8t, and the size of the pellet is Φ1
3-8t. The occupancy of the working surface of the diamond layer was set to 80% in terms of the area ratio (working surface / total working surface) to the total working surface of the lap platen.

The diamond wrap surface plate is mounted on a double-sided lapping machine having a mechanism for holding a workpiece with a work carrier that revolves while rotating, and is trued with a diamond dress carrier to reduce the flatness of the diamond layer to 3 degrees.
μm or less, after dressing with a GC square whetstone,
WC-Co based cemented carbide substrate with dimensions of outer diameter Φ100
The effect of the present invention was confirmed by processing a material having a thickness of 0.3 mm and a thickness of 0.3 mm and comparing the performance with a conventional diamond wrap plate having pellets fixed on the entire surface. The rotation speed of the diamond wrap platen is 65r. p. When processing was performed at a processing pressure of 0.5 kgf / cm ^{2 on the} workpiece, the processing speed of this embodiment was about five times that of the conventional product, and the conventional product required dressing in the middle of processing. In the example, the processing could be continued without dressing.

Example 4 A binder composed of 40% by weight of copper, 32% by weight of tin, and 18% by weight of graphite and diamond abrasive grains (average particle size: 2.0 μm) were mixed so as to have a concentration of 20. Then, a diamond layer was formed in a ring shape and a pellet shape, and these were fixed to a cast iron platen main body by an adhesive or soldering to produce a diamond wrap platen. The size of the ring-shaped outer diamond layer is Φ600
-5w-8t (Φ: outer diameter, w: width, t: thickness, unit: m
m, the same applies hereinafter), the size of the ring-shaped inner peripheral diamond layer is Φ230-5w-8t, and the size of the pellet is Φ1
3-8t. The occupancy of the working surface of the diamond layer was set to 70% in terms of the area ratio (working surface / total working surface) to the entire working surface of the lap platen.

This diamond wrap surface plate is mounted on a double-sided lapping machine having a mechanism for holding a workpiece with a work carrier that revolves while rotating, and is trued with a diamond dress carrier to reduce the flatness of the diamond layer to 2.
μm or less, after dressing with a GC square whetstone,
The effect of the present invention was confirmed by processing AlTiC (Al ₂ O ₃ —TiC) and comparing the performance with a conventional diamond wrap platen having pellets fixed on the entire surface. The rotation speed of the diamond wrap platen is 65r. p. m, processing was performed at a processing pressure of 1 kgf / cm ^{2 on the} workpiece. In this example, the processing speed was about six times that of the conventional product, and the sharpness of the conventional product was sharply reduced immediately after the start of processing, and the processing speed was reduced. Although the continuation became difficult, the working example could be continued without dressing.

Example 5 A binder composed of 40% by weight of copper, 32% by weight of tin, and 18% by weight of graphite and diamond abrasive grains (average particle diameter: 20 μm) were mixed so as to have a concentration of 20, Diamond layers were formed in a ring shape and a pellet shape, and these were fixed to a cast iron platen main body by an adhesive or soldering to produce a diamond wrap platen. The size of the ring-shaped outer diamond layer is Φ600
-5w-8t (Φ: outer diameter, w: width, t: thickness, unit: m
m, the same applies hereinafter), the size of the ring-shaped inner peripheral diamond layer is Φ230-5w-8t, and the size of the pellet is Φ1
3-8t. The occupancy of the working surface of the diamond layer was set to 70% in terms of the area ratio (working surface / total working surface) to the entire working surface of the lap platen.

This diamond wrap surface plate is mounted on a double-sided lapping machine having a mechanism for holding a workpiece with a work carrier that revolves while rotating, and is trued with a diamond dress carrier to reduce the flatness of the diamond layer to 2.
μm or less, after dressing with a GC square whetstone,
The effect of the present invention was confirmed by processing a single crystal sapphire substrate and comparing the performance with a conventional diamond wrap plate having pellets fixed on the entire surface. The rotation speed of the diamond wrap platen is 50 r. p. When processing was performed at a processing pressure of 1 kgf / cm ^{2 on the} workpiece, the processing speed of this embodiment was about 10 times that of the conventional product, and the processing speed of the conventional product was slow, and dressing was frequently performed during the processing. Although required, the working example could be continued without dressing.

EFFECT OF THE INVENTION Planar processing of cemented carbide, cermet, altic, glass, sapphire, ceramics, quartz, silicon, ferrite, neodymium magnet, samarium cobalt, etc. with extremely high precision, efficiency and almost no dressing. to enable. Further, it is considered that the present invention is sufficiently applicable to high-precision planar processing of vapor-phase synthetic diamond.

[Brief description of the drawings]

FIG. 1 is a partial plan view showing an embodiment of the present invention.

FIG. 2 is a partial plan view showing another embodiment.

[Description of Signs] 1 Main body of platen 2 Diamond layer pellet 3 Ring-shaped outer diamond layer 4 Ring-shaped inner diamond layer 5 Arc-shaped diamond layer P Diamond wrap platen

Claims (4)

[Claims] 1. A diamond layer formed by bonding diamond abrasive grains with a bonding material, which is used by being attached to a grinding machine having a mechanism for holding a workpiece with a work carrier revolving while rotating and performing plane processing. A diamond lap plate fixed to the entire surface of the lap plate, wherein the occupancy of the working surface of the diamond layer is an area ratio to the entire processed surface of the lap plate (work surface / total processed surface).
Is set in the range of 40% to 80%, and the composition of the binder is 33 to 75% by weight of copper;
A diamond wrap plate comprising 18 to 55% by weight of tin and 2 to 20% by weight of graphite. 2. The diamond according to claim 1, wherein the workpiece is a hard and brittle material such as cemented carbide, cermet, altic, glass, sapphire, ceramics, quartz, silicon, ferrite, neodymium magnet, and samarium cobalt. Lap surface plate. 3. The workpiece is a WC-base cemented carbide, and its dimensions are for a substrate of a superabrasive cutting wheel having an outer diameter of Φ10 mm to Φ300 mm and a thickness of 0.01 mm to 3 mm. The diamond wrap surface plate according to 1. 4. The diamond layer according to claim 1, wherein the diamond abrasive has an average particle diameter of 20 μm to 800 μm and a degree of concentration of 5 μm.
4. The method according to claim 1, wherein the number is from 100 to 100.
The described diamond wrap surface plate.