JPH0739077B2 - Resin bond grinding wheel - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superabrasive resin bond grinding wheel which can be suitably used for grinding cemented carbide and tool steel.

[0002]

2. Description of the Related Art Conventionally, a phenol resin has been used as a binder for an abrasive layer of a superabrasive resin bond grinding wheel such as diamond and CBN, but the heat generated at the grinding point during processing causes the abrasive particles to It is transmitted and deteriorates the resin in the vicinity where it is held, thereby eliminating the function of holding the abrasive grains and shortening the life of the grinding wheel. In particular, unlike dry grinding, dry grinding does not use a coolant, so that the grinding wheel cannot be sufficiently cooled, and therefore the phenomenon of abrasive grain loss due to grinding heat is significant. For this measure, it has excellent heat resistance as an alternative to phenolic resin,
Various applications have been investigated for application of a resin that does not deteriorate the holding power of abrasive grains due to heat generation, but the heat resistance of the resin itself is limited, and a sufficient resin has not been found.

On the other hand, together with efforts to improve the heat resistance of the resin bond, the thermal conductivity of the entire abrasive grain layer is improved to prevent the deterioration of the abrasive grain holding force due to the deterioration of the resin in the vicinity of the abrasive grains due to the grinding heat, and to improve the heat of the resin bond In order to enhance the emission, a resin bond mixed with a metal filler having good thermal conductivity is disclosed in, for example, JP-A Nos. 53-51587 and 53-53.
No. 63693 is disclosed.

[0004]

However, in order to improve the thermal conductivity of the abrasive grain layer by adding the metal powder, it is necessary to add a considerable amount to the binder, and as a result, the abrasive grain layer is added. Becomes harder, and it becomes impossible to maintain the elasticity that is peculiar to a resin bond wheel. As a grinding wheel, the life is extended, but the sharpness is remarkably poor, and the problems such as increased grinding noise, chattering of the grinding surface, and deterioration of surface roughness. There is.

The problem to be solved in the present invention is to maintain the sharpness, which is a characteristic of the resin bond, in the addition of metal powder for improving the thermal conductivity of the abrasive grain layer.

[0006]

According to the present invention, a filler forming a resin bond is thinly coated with a metal having good thermal conductivity to maintain sharpness and improve its thermal conductivity.

Table 1 shows the thermal conductivity of phenolic resin and various metals.

[0008]

[Table 1]

In the present invention, the filler has a particle size of 12 to 12
Any metal-coated phenolic resin cured product with a diameter of 36 μm can be used, and the coated metal is copper with good thermal conductivity,
Silver, gold, nickel, iron, tin and their alloys can be preferably applied, and 0.2, by means such as electroless plating.
The coating is applied to a thickness of -14 μm. At this time, a coating having a thickness of more than 14 μm causes the same adverse effect as in the case of blending metal particles, and therefore should be contained within a range of 14 μm or less.

The resin particles coated with a metal are used as a metal in the wheel so that the thermal conductivity of the abrasive layer is 40 W / mK or more, which is the same value as in the conventional technique, that is, the case where metal powder is added. It is necessary to contain 7% by volume or more of the whole abrasive layer, but addition in excess of 19% by volume causes the same adverse effect as in the case of compounding metal particles, so it should be contained within the range of 7 to 19% by volume.

The particle size of the filler, the film thickness of the metal coating, and the amount of addition are adjusted within the above ranges to prepare a compound having a predetermined thermal conductivity in the abrasive layer.

FIG. 1 is a partially enlarged view showing a sectional structure of a super abrasive grain resin bond grinding wheel according to the present invention. Reference numeral 1 is an abrasive material such as a nickel-coated CBN abrasive material and a diamond abrasive material, and 2 is a phenol resin. And 3 are metal coated resin particles.

[0013]

In the superabrasive resin bond grinding wheel to which the resin filler having a thin metal coating according to the present invention is added, the binder does not become hard in view of the amount added as a metal, and the characteristics of the resin bond are The thermal conductivity can be improved while maintaining good sharpness and elasticity.

Furthermore, in preparing the resin bond,
The resin filler with a thin metal coating has a particle size equivalent to 12 to 36 μm as compared with phenolic resin, and the difference in specific gravity is small, resulting in a better dispersed state than when using metal particles and thermal conductivity. Is improved, the dissipation of heat generated at the grinding point during processing is improved, the temperature of the resin itself in the vicinity of the abrasive material does not rise extremely, and a decrease in abrasive grain holding force due to thermal deterioration is prevented.

[0015]

Examples Example 1 A superabrasive resin bond grinding wheel having the composition shown in Table 2 was prepared and a grinding test was conducted.

Prior to the grinding test, a test piece having the same composition as that of the tested wheel and having a diameter of 10 mm and a thickness of 2 mm was prepared and the thermal conductivity thereof was measured. I confirmed that it was close to the wheel.

Table 2 shows the composition and thermal conductivity of the test grinding wheel of Example 1.

[0018]

[Table 2]

The conditions for carrying out the grinding test are shown below.

(1) Test grinding wheel specifications, dimensions Specifications: As shown in Table 2 Diameter: 100 mm Width: 3 mm (2) Grinding conditions Grinding method: Dry tool grinding Machine used: Makino tool grinder CFIA-40 type wheel circumference Speed: 1200 m / min Table speed: 1.5 m / min Depth of cut: 0.03 mm Grinding fluid: Dry Material: JIS SKH-57 (3) Work material Dimensions: Width 6 mm, length 20 mm Rectangle Hardness: HRC 65 Table 3 shows the grinding result.

[0021]

[Table 3]

The wheel to which the nickel-coated resin powder was added (Example 1) had a significantly improved grinding ratio as compared with the wheel to which the cured phenol resin was added (Comparative Example 2). The increase in power consumption is slight and the grinding resistance is unchanged. From this, it can be seen that by adding the nickel-coated resin filler, the thermal conductivity of the abrasive layer was improved but the sharpness was not lost, and the sharpness was maintained while improving the life of the wheel. .

Also, nickel powder filler (Comparative Example 1)
Power consumption is significantly lower and sharpness is better than other wheels.

By adding the nickel-coated resin filler, the life of the wheel was improved without reducing the sharpness of the wheel.

Example 2 A superabrasive resin bond grinding wheel having the composition shown in Table 4 was prepared and a grinding test was conducted. Example 1 also in this test
The thermal conductivity was measured in the same manner as above to obtain a satisfactory intended value.

[0026]

[Table 4]

The grinding test conditions are shown below.

(1) Grinding test wheel specifications, dimensions Specifications: As shown in Table 4 Diameter: 150 mm Width: 2 mm (2) Grinding conditions Grinding method: Wet creep feed grinding Machine used: Okamoto surface grinder CFG-52B type wheel Peripheral speed: 1600 m / min Table speed: 120 mm / min Depth of cut: 1 mm Grinding fluid: Water-soluble 2 types (3) Work material: JIS G2 Dimensions: width 50 mm, length 100 mm rectangle Hardness: Hv 1300 Table 5 The results are shown.

[0029]

[Table 5]

The wheel to which the copper-coated resin filler was added (Example 2) exhibited a higher grinding ratio than the wheel to which the phenol resin cured product was added (Comparative Example 4), and the abrasive grains generated by the heat generated during processing were It can be seen that the falling off is prevented and the abrasion of the abrasive layer is suppressed.

Further, the power consumption is lower than that of the wheel made of the copper powder filler (Comparative Example 3), which means that the sharpness is not lost by the addition of the filler.

From the above, by adding the copper-coated resin filler, the life of the wheel was improved without reducing the sharpness of the wheel.

[0033]

According to the present invention, the life of the superabrasive resin bond grinding wheel can be extended without deteriorating the sharpness, and the machining efficiency can be improved and the machining cost can be reduced.

Further, problems such as an increase in grinding noise, chatter of the ground surface, and deterioration of surface roughness can be solved.

[Brief description of drawings]

FIG. 1 is a partially enlarged view showing a cross-sectional structure of a super abrasive grain resin bond grinding wheel according to the present invention.

[Explanation of symbols]

 1 Abrasive material 2 Binder 3 Metal coated resin particles

Claims (1)

[Claims] 1. Thermal conductivity as a resin bond filler
Is 70 W / mK or more, and the resin particles coated with a thickness of 0.2 to 14 [mu] m are used as the metal, and
A super-abrasive resin bond grinding wheel characterized by being added in an amount of up to 19% by volume .