JP2000053463A - Jig for can manufacturing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a jig for can manufacturing having enhanced wear resistance at a reduced production cost. SOLUTION: Oxide particles contg. Ti or Mg are dispersed in grains or grain boundaries forming an aluminous sintered compact contg. 90-99 wt.% Al2O3 and 0.2-5 wt.% (expressed in terms of TiO2) Ti or an aluminous sintered compact contg. 90-99 wt.% Al2O3, 0.2-5 wt.% (expressed in terms of TiO2) Ti and 0.1-3 wt.% (expressed in terms of MgO) Mg.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a can-making jig for drawing an end of a can body to fasten a can lid.

[0002]

2. Description of the Related Art Conventionally, juice cans, beer cans, canned cans and the like have used two-piece cans or three-piece cans having a can lid fastened to a can body. However, if the wound part of the can lid has a diameter larger than the diameter of the can body and protrudes, the sealed parts will abut each other, so if a large number of cans are accommodated in a corrugated package, Since there is a gap between the can bodies and waste of the accommodating space occurs, the end of the can body is squeezed so that the can bodies come into contact with each other, so that the efficiency of accommodating the can in the cardboard packaging is improved. .

[0003] The drawing of the end of the can body will be described with reference to Figs. FIG. 4 is a cross-sectional view of a jig for can and a can body, and FIG. 5 is an enlarged cross-sectional view of a main part of the jig for can. 101 is a female type, 102 is a male type, and 103 is a can body.
Insert and place. A gap is provided between both the female mold 101 and the male mold 102, and the end of the can body 103 faces the opening of the gap. A guide hole 104 for receiving an end of the can body 103 is formed on the inner surface of the female mold 101, and the guide hole 104 is formed along the guide hole 104.
When 103 enters, an inclined hole 105 having a smaller diameter is connected. Behind this, there is provided a throttle hole 106 for narrowing the end of the can body 103 to a required diameter.

A guide flange 107 is formed on the male mold 102, and its outer diameter is set to a dimension so as to be the inner diameter of the end of the can body 103 after drawing. Further, the axial length of the guide flange 107 is the total length of the front end portions of the guide hole 104, the inclined hole 105, and the throttle hole 106 of the female die 101.

Then, as shown in FIG. 4, while rotating the can body 103 around the central axis 108, the female mold 101 and the male mold 102 are rotated.
Then, the end of the can body 103 is guided to the guide hole 104 of the female mold 101, reaches the inclined hole 105, and is reduced in diameter inward. Further, when the end of the end of the can body 103 is reduced in diameter to a required diameter, the end of the end then balances with the guide flange 107 of the male mold 102, and the gap 109 between the throttle hole 106 and the guide flange 107 is formed. And the end of the can body 103 is reduced to a required size and shape as shown by a two-dot chain line in FIG. Thereafter, the can body 103 is retracted, and the drawing of the end of the can body 103 is completed.

Conventionally, the female mold 101 and the male mold 102 have been formed of tool steel (die steel) or carbide.
There was a problem that the contact surface with the abrasion was severely worn. To solve this problem, it has been proposed to use ceramics and other materials (see Japanese Patent Application Laid-Open No. Sho 62-54530).

[0007]

However, even with this proposed technique, it has not been possible to increase the wear resistance to a satisfactory level. Therefore, if the contact surface of the female mold 101 or the male mold 102 is worn and roughened, the rubbing part of the can body 103 will be damaged, the coating film covering the can body 103 will be damaged, and the coating film will come off. Then, rust was generated and the appearance was impaired.
In addition, there is also a problem that the material is corroded and perforated to make the contents dirty and flow out.

[0008] When the rubbing portion of the can body 103 is scratched as described above, it is determined to be a defective product. Furthermore, the necessity of replacing the female mold 101 and the male mold 102 increased the cost, and the replacement reduced the work efficiency, thereby increasing the production cost.

Accordingly, the present invention has been completed in view of the above circumstances, and an object of the present invention is to provide a jig for can making in which abrasion resistance is further improved and production cost is reduced.

[0010]

The jig for a can according to the present invention comprises:
Al ₂ O ₃ 90~99% by weight, in terms of Ti to TiO ₂ was composed of an alumina sintered body containing 0.2 to 5 wt%, the crystal grains and grain boundaries which make this alumina sintered body It is characterized in that oxide particles containing Ti are dispersed.

Another jig for cans of the present invention is Al ₂ O ₃ 9
0-99% by weight, in terms of Ti to TiO ₂ 0.2 to 5
% Of Mg and 0.1 to 3% by weight of Mg in terms of MgO. The oxide particles containing Mg are dispersed in crystal grains and grain boundaries forming the alumina-based sintered body. It is characterized by having made it.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
This will be described with reference to FIG. 1 is a sectional view of a jig for a can and a can body, FIG. 2 is an enlarged sectional view of a main part of the jig for a can, and FIG. 3 is an enlarged sectional view of a main part of another jig for a can.

In FIGS. 1 and 2, a male mold 2 is inserted and arranged in a female mold 1, and 3 is a can body.
A guide hole 4 for receiving the end of the can body 3 is formed on the inner surface of the female mold 1, and a small-diameter inclined hole 5 is further formed, whereby the end of the can body 3 is gradually reduced in diameter. A throttle hole 6 for narrowing the end of the body 3 to a required diameter is formed.

The inclination angle α1 of the inclined hole 5 is preferably 15 to 45 °, and more preferably 25 to 37 ° in order to gradually reduce the diameter of the can body 3. In addition, an arc R1 of about 0.05 to 2 mm can be formed at the opening of the guide hole 4 to guide the can body 3 without damaging it, and preferably 0.1 to 1 mm.

Further, if a concave arc R2 of about 1 to 10 mm is formed in a continuous portion between the guide hole 4 and the inclined hole 5, it is sufficient to start reducing the diameter of the can body 3 smoothly. mm is good.

Further, in the continuous portion between the inclined hole 5 and the throttle hole 6, the arc R3 is reduced to about 0.5 to 10 mm so as not to damage the can body 3 when the can body 3 starts to be reduced to a predetermined outer diameter. The thickness is preferably formed, and preferably about 2 to 2.5 mm.

The guide flange 7 of the male mold 2 is
In order to gradually reduce the diameter to form a predetermined diaphragm outer diameter, the diameter is set so as to become smaller as it goes forward in the axial direction, and the inclination angle α2 is formed to 1 to 55 ′, and particularly to 15 ′.
The degree is preferred. Further, an arc R4 of about 0.5 mm is preferably formed at a corner portion where the end of the can body 3 enters so as not to damage the can body 3.

Further, the guide hole 4 and the inclined hole 5 of the female mold 1 are provided.
, Drawn holes 6 and arcs R1, R2, R3, guide flange 7 of male mold 2 and can body 3 of arc R4
It is preferable to make the surface smooth (Rmax) to 0.1 to 0.8 μm. As a result, the can body 3 is not damaged, and a smooth mirror surface with a surface roughness (Rmax) of preferably 0.1 to 0.3 μm is preferably finished.

In the jig for a can having such a configuration, the female mold 1 and the male mold are rotated while rotating the can body 3 about the central axis 8.
2, the end of the can body 3 is guided to the guide hole 4 of the female die 1 to reach the inclined hole 5, and the diameter gradually decreases inward. The tip of the end of the can body 3 abuts against the guide flange 7 of the male mold 2 and is guided by the gap 9 formed by the throttle hole 6 and the guide flange 7. The end of the can body 3 is shown in FIG. It is narrowed down to the required dimensions and shapes as shown. Thereafter, the can body 3 is retracted, and the drawing of the end of the can body 3 is completed.

In addition to the above-described structure, the female mold 1 may be formed with a slope having an inclination angle α3 of about 1 to 5 ° in the guide hole 4 in order to facilitate reception of the can 3 as shown in FIG. Good.

In the present invention, these female molds 1 and / or
Alternatively, the male mold 2 is composed of an alumina-based sintered body, and the surface portion thereof includes Ti inside the alumina crystal grains and over the grain boundaries.
By precipitating and dispersing oxide particles containing, residual stress is formed at quasi-grain boundaries and minute regions, the hardness is remarkably improved, and wear due to shedding can be effectively suppressed. The chipping property is greatly improved, and a longer life is achieved.

In order to produce an alumina-based sintered body in which oxide particles containing Ti are dispersed as described above, a compound containing Ti and other additives are added to alumina powder, and the compact of the mixture is reduced. Heating in an atmosphere, thereby dissolving Ti in Al ₂ O ₃ , and then heating in an oxidizing atmosphere to turn Ti into an oxide, and an oxide containing Ti in crystal grains and at grain boundaries. The particles are precipitated and dispersed.

Instead of such a production, a molded body made of a mixture containing a compound containing Ti and Mg and other additives is heated in an oxidizing atmosphere to obtain Ti and Mg.
Is dissolved in Al ₂ O ₃ , and then heat-treated in a reducing atmosphere to dissolve Ti in Al ₂ O ₃ and to use Mg as an oxide in the crystal grains and in the grains of Al ₂ O _3. It may be precipitated and dispersed in the field.

The oxide phase containing Ti and Mg is, for example, TiO ₂ , Al ₂ TiO ₅ , RE ₂ Ti ₂ O
₇ (RE is a rare earth element), MgO, MgAl ₂ O ₄ etc., all of which have excellent chemical and thermal stability, do not impair oxidation resistance, and significantly improve high-temperature strength and high-temperature hardness.
As a result, a jig for can-making with excellent wear resistance and long life is provided.

On the other hand, when the Ti content of the alumina sintered body is small, the volume fraction of the dispersed particles is small, and the effect of improving the wear resistance is small. When the Ti content is large, coarse Al ₂ A TiO ₅ phase is formed, and minute cracks are generated due to a difference in thermal constant with the crystal grains, thereby reducing the chipping resistance of the jig for can making. Therefore, the Ti content in the sintered body is reduced to TiO
0.2 to 5% by weight, preferably 0.5 to 3% by weight in terms of ₂ .

With respect to the Mg content, if the Mg content is small, the volume fraction of the dispersed particles is small, and the effect of improving the wear resistance is reduced. If the Mg content is large, sintering is hindered, and a dense sintered body is formed. It is difficult to obtain. Therefore, the Mg content is changed to MgO
0.1 to 3% by weight, preferably 0.1 to 2% by weight
To

With respect to the crystal grain size of the Al ₂ O ₃ mother phase, if the average grain size is 10 μm or less, preferably 5 μm or less,
This is good in that the strength is increased to improve the fracture resistance.

When the size of the oxide particles containing Ti or Mg dispersed in the crystal phase of Al ₂ O ₃ and at the grain boundaries is small, the distance between the dispersed particles is small and the gap between the dispersed phase and the parent phase is small. By maintaining the crystalline consistency, the strain at the interface is large, and a large hardening effect is brought about. In order to sufficiently exhibit the effect of improving the abrasion resistance, the average particle diameter of the oxide particles containing Ti or Mg is preferably 0.2 μm or less.

In the alumina sintered body having such a configuration, the oxide particles containing Ti or Mg may be uniformly dispersed from the surface to the inside, but at least a depth of 0.01 mm or more from the surface of the ceramic. A wear-resistant layer in which the above-mentioned oxide particles containing Ti or Mg are dispersed may be formed in the previous region. From the viewpoint of improving the service life, the thickness of the wear-resistant layer is preferably 0.02 μm or more.

Further, rare earth elements, Zr, Hf, Mo, W
Is added, thereby increasing the chemical stability, suppressing the crystal grain growth of alumina, and improving the strength of the jig for cans. When an oxide of Si is added, the anisotropic growth of alumina crystals is promoted, and the toughness is significantly improved. The total amount of the above oxides is 0.3 to 5
It is good to make it by weight%.

As described above, an alumina-based sintered body in which oxide particles containing Ti or Mg are dispersed in crystal grains and in grain boundaries, and further added with oxides of rare earth elements, Zr, Hf, Mo, and W, , The content ratio of the Al ₂ O ₃ component is 90
It may be up to 99% by weight.

In order to produce the alumina-based sintered body having the above structure, first, alumina powder having an average particle size of 0.1 to 1 μm is added to
Predetermined amounts of the Ti-containing compound and the Mg-containing compound are added and mixed. The compound may be any of oxide powder, metal powder, organic salts, inorganic salts and a solution thereof. The above mixture is formed into an arbitrary shape by a desired forming means, for example, a die press, a cold isostatic press, a casting, an injection molding, an extrusion molding, or the like. Next, the formed body is subjected to a known sintering method, for example, a hot press method, a normal pressure sintering method, a gas pressure sintering method, a microwave heating sintering method, and a hot isostatic pressure (HIP) treatment after these sintering. Sintering is performed by various sintering techniques, such as after glass sealing (HIP).

According to the present invention, in the calcination, heat treatment is performed in a reducing atmosphere in which Ti can be dissolved in alumina crystals, and then heat treatment is performed in an oxidizing atmosphere in which Ti can be precipitated as an oxide from the solid solution. Alternatively, heat treatment is performed in an oxidizing atmosphere in which Ti and Mg can form a solid solution in alumina crystals, and then heat treatment is performed in a reducing atmosphere in which Mg can be deposited as an oxide from the solid solution. The compact is fired densely by using any of the heat treatment steps described above. However, heat treatment is performed after such dense firing, or HIP is performed after solid solution and precipitation to densify. Good.

By adding a Ti compound to alumina,
When Ti is heat-treated in a reducing atmosphere, the ionic valence of Ti becomes 3+, the solubility in alumina crystals increases, and a solid solution is formed. Then, by treating this solid solution in an oxidizing atmosphere, the ionic valence of Ti becomes 4+, and the solubility in the alumina crystal is reduced.
i is mainly deposited as TiO ₂ and Al ₂ TiO ₅ .

When a compound containing Ti and Mg is added to alumina at the same time, if the treatment is performed in an oxidizing atmosphere, T
i and Mg can be simultaneously dissolved in alumina crystals at the same molar ratio. Then, by treating this solid solution in a reducing atmosphere, the ionic valence of Ti becomes 3+, and the Ti alone is preferentially dissolved in alumina. Since Mg alone cannot be dissolved in alumina, it is mainly deposited in the form of MgAl ₂ O ₄ . Examples of such a reducing atmosphere include a hydrogen-containing atmosphere, an inert gas atmosphere, and a high vacuum atmosphere having an oxygen partial pressure of 10 ⁻⁶ atm or less. The treatment in the oxidizing atmosphere is performed in the air.

Furthermore, if the temperature during the solid solution or precipitation treatment is low, the required structure is not formed, and the alumina crystal grains and precipitated particles are coarsened. Therefore, regarding the temperature at the time of solid solution or precipitation,
It is good to make it in the range of 0 to 1600 ° C.

Thus, according to the jig for a can of the present invention, since the female mold 1 and / or the male mold 2 is formed of the above-mentioned alumina sintered body, excellent wear resistance (Vickers hardness: 1600 kg / mm or more) and high toughness (fracture toughness value (K1C): 4 MPa√m or more), thereby enabling long-term use.

[0038]

Next, embodiments of the present invention will be described in detail. (Example 1) Female mold 1 and male mold 2 were made of various ceramic materials. Alumina (Al ₂ O ₃ ) powder and titanium oxide (TiO ₂ ) powder were prepared as raw material powders at the composition ratios shown in Table 1, press-formed at a pressure of 1 ton / cm ² , and then 3 ton / cm ² Cold isostatic pressing (CIP)
To obtain a molded body. This compact was fired for 2 hours under the firing conditions shown in Table 1 and then heat-treated for 2 hours under the heat treatment conditions shown in Table 1.

[0039]

[Table 1]

These sintered bodies were processed into a mirror surface, and precipitated particles in alumina crystal particles were confirmed on a scanning electron microscope photograph, and α-Al ₂ in the sintered bodies was measured by X-ray diffraction measurement.
Crystals other than O ₃ were identified.

The flexural strength was measured according to JIS-R1601, and the fracture toughness (KIC) was measured by Vickers indentation method.
According to JIS-Z2244, Vickers hardness (load 1)
kg) was measured for the wear rate by the pin-on-disk method (load 1 kg, speed 5 m / sec, 5 minutes).

In addition, conventional zirconia (as a main component, Z
rO, slightly containing Al ₂ O ₃ and Y ₂ O ₃ ), silicon nitride (Si ₃ N ₄ as a main component, slightly Al ₂ O ₃ and Y ₂ O)
₃ ), and the same measurement was performed for alumina. The results shown in Table 1 were obtained.

As is clear from Table 1, the sample N of the present invention
o. As for Nos. 3 to 5, it can be seen that the abrasion speed is significantly reduced.

Example 2 In this example, as shown in Table 2, magnesium oxide (MgO) was further added, and various samples were similarly prepared. You can see that.

[0045]

[Table 2]

(Example 3) Sample Nos. Shown in Tables 1 and 2
3-8 and conventional zirconia, silicon nitride, alumina,
Further, using carbide and tool steel (die steel), each one
When 100,000 cans were manufactured and the number of scratches and the degree of wear were examined, the results shown in Table 3 were obtained.

The number of scratches is measured by rotating the can body 3 and using a magnifying glass to measure the entire outer peripheral surface (mainly, the reduced diameter portion). The degree of wear was measured by a micrometer using the amount of decrease (m) in the guide hole 4 of the female mold 1.
m) was measured.

[0048]

[Table 3]

As is clear from this table, the use of the jig for can of the present invention significantly reduces the number of scratches on the can body, and also significantly reduces the degree of wear of the female mold.

[0050]

As described above, the jig for cans of the present invention is
The abrasion resistance is remarkably improved by forming the alumina-based sintered body in which the oxide composition containing Ti and Mg is dispersed by defining the component composition, thereby preventing the rubbing portion of the can body from being damaged. In addition, the coating film covering the can body was not damaged, and the coating film did not peel off. Therefore, the appearance was maintained, and the contents did not leak.

In addition to using the can making jig of the present invention to improve the yield of can products, the can making jig itself can be used for a long period of time, and its replacement frequency is reduced. As a result, production costs could be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a can body and a jig for can making of the present invention.

FIG. 2 is an enlarged sectional view of a main part of the jig for can making of the present invention.

FIG. 3 is an enlarged sectional view of a main part of another jig for can making of the present invention.

FIG. 4 is a sectional view of a can body and a conventional jig for can making.

FIG. 5 is an enlarged sectional view of a main part of a conventional can-making jig.

[Explanation of symbols]

 Reference Signs List 1 female type 2 male type 3 can body 4 guide hole 5 inclined hole 6 throttle hole 7 guide flange 9 gap

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Fumio Matsunaga 1-1, Yamashita-cho, Kokubu-shi, Kagoshima Inside the Kokubu Plant (72) Inventor Toshiaki Kiyama 1-1-1, Yamashita-cho, Kokubu-shi, Kagoshima Kyocera Corporation Inside the Kokubu Plant of Shikisha Co., Ltd. (72) Inventor Kuyoshi Matsuyama 1-1-1, Yamashita-cho, Kokubu-shi, Kagoshima Kyocera Co., Ltd. F-term in the Kokubu Plant Co., Ltd.

Claims (2)

[Claims] (1) 90 to 99% by weight of Al ₂ O ₃ ,
It is composed of an alumina sintered body containing 0.2 to 5% by weight in terms of O ₂ , and oxide particles containing Ti are dispersed in crystal grains and grain boundaries constituting the alumina sintered body. Characteristic jig for cans. 2. An Al ₂ O ₃ content of 90 to 99% by weight and Ti being Ti
An alumina sintered body containing 0.2 to 5% by weight in terms of O ₂ and 0.1 to 3% by weight in terms of Mg in terms of MgO;
A can-making jig characterized in that oxide particles containing Mg are dispersed in crystal grains and grain boundaries forming the alumina-based sintered body.