JPH10251032A - Alloy for glass molding die, and glass molding die manufactured from the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain prolonged service life by improving the wear resistance of an oxide film of a glass molding metallic die. SOLUTION: This alloy for glass molding metallic die contains, by weight, >=4% to <12% Al, >=10% to <25% Ni, >=0.02% to <1.0% one or more kind of rare earth element, <8% Fe, <4% Si and the balance Cu and inevitable elements. Alternatively, the alloy for glass molding metallic die contains by weight >=4% to <12% Al, >=10% to <25% Ni, >=0.02% to <1.0% one or more kinds of rare earth elements, >=0.05 to <0.8% Zr, <8% Fe, <4% Si and the balance Cu with inevitable elements. The glass molding metallic die made of the alloy has the rigid oxide film on the metallic surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an alloy used for a glass forming mold and a mold made of the alloy.

[0002]

2. Description of the Related Art A glass forming mold is generally made of cast iron, heat-resistant steel or the like. In the glass molding mold made of these materials, when the inserted high-temperature molten glass contacts the mold surface, the glass and the mold surface react,
The mold release of the glass is poor, and the surface properties of the product are deteriorated.

[0003] For this reason, conventionally, it is customary to operate while applying an oil-based release agent mainly composed of graphite to the surface of a glass molding die. However, this release agent burns after oiling and deteriorates the work environment, or causes quality deterioration due to the adhesion of graphite to the glass surface,
There is a strong demand for so-called mold-free coating without using a mold release agent.

The present inventors have already disclosed Japanese Patent Application Laid-Open No. 64-229.
Japanese Patent No. 706 discloses a high-temperature alloy which is excellent in high-temperature oxidation resistance in which an alumina film is formed on an alloy surface by heat treatment in an oxidizing atmosphere. Then, JP-A-06-10079, JP-A-06-279944, JP-A-08-225904, and JP-A-08-225904.
No. 293490 proposes an alloy and a mold that satisfy the requirements as a glass forming mold, that is, have good thermal conductivity, high high-temperature hardness, excellent corrosion resistance, and a strong alumina coating. .

[0005] However, these alloys contain Fe phase and C
It is a two-phase alloy consisting of a u-phase. It must be heated to a high temperature necessary for melting Fe during melting.
Since the solidification temperature of the u-phase greatly differs, there is a problem that defects are likely to occur during casting. Therefore, there has been a demand for the development of a mold that can be formed by using an alloy that can be easily melted and cast without applying a release agent.

On the other hand, Japanese Unexamined Patent Publication No. 59-502111 and Japanese Unexamined Patent Publication No. 2-228441 disclose an aluminum bronze-based alloy which is an alloy containing only a Cu phase and which can be easily melted and cast, and a glass production metal made therefrom. The type is disclosed. However, since the alloy and the mold are not intended for mold release agent-free molding and cannot form a strong oxide film on the surface which is a feature of the present invention,
Molding without release agent was impossible.

[0007]

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems relating to the mold, and is capable of producing a mold having excellent performance at a low cost, which can be formed without applying a release agent. It is intended to make it possible.

[0008]

Means for Solving the Problems The present invention is as follows. (1) Al 4% or more and less than 12% by weight, Ni
10% or more and less than 25%, one or more rare earth elements or more 0.02% or more and less than 1.0%, Fe less than 8%, S
i. An alloy for a glass molding die, comprising less than 4%, and the balance being Cu and unavoidable elements. (2) Al 4% or more and less than 12% by weight, Ni
10% or more and less than 25%, one or two or more rare earth elements and 0.02% or more and less than 1.0%, Zr 0.05% or more and less than 0.8%, Fe 8% or less, and Si less than 4%, An alloy for a glass molding die, comprising a balance of Cu and an unavoidable element. (3) A glass molding die having a strong oxide film on the surface of the die made of the alloy according to (1) or (2). (4) The glass molding die according to (3), wherein the oxide film is an oxide of Al and Zr. (5) The mother alloy is melted and cast to produce an alloy for a glass molding die, which is machined into a die, and the die is held at a temperature of 800 ° C. or more for 1 hour or more, A method for producing a glass molding die, wherein a strong oxide film is formed on the surface. (6) The alloy for glass molding die is Al 4 in weight ratio.
% To less than 12%, Ni 10% to less than 25%, one or two or more rare earth elements 0.02% to less than 1.0%, Fe less than 8%, Si less than 4%, balance Cu and inevitable elements (5) characterized by comprising:
3. The method for producing a glass molding die according to item 1. (7) The alloy for glass molding die is Al 4 in weight ratio.
% To less than 12%, Ni 10% to less than 25%, one or two or more rare earth elements 0.02% to less than 1.0%, Zr 0.05% to less than 0.8%, Fe less than 8%, (5) The method for producing a glass molding die according to the above (5), wherein the glass contains less than 4% of Si and the balance is Cu and inevitable elements.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. In general, glass is formed by cutting off molten glass at a temperature of 1000 ° C. or higher, inserting the cut glass into a mold, and bringing the molten glass into close contact with the mold surface by a blowing or pressing process. Above all, in the production of a typical glass bottle, the molten glass is dropped into the mold at a high speed in order to achieve close contact with the mold in the first stage. In other words, the mold surface is subjected to mechanical abrasion during insertion of the molten glass, in addition to the chemical reaction with the molten glass. The application of the release agent in the current process is to prevent the chemical reaction between the molten glass and the mold surface and to ensure release properties, but at the same time it also has the effect of reducing mechanical wear due to lubrication. .

Therefore, as compared with a conventional mold used while applying a release agent, a mold that performs molding without applying a release agent is required to have stricter conditions in terms of material. In particular, JP-A-06-10079 and JP-A-06-10079, which were invented by the present inventors.
Japanese Patent Application Laid-Open No. 279944/1996, Japanese Patent Application Laid-Open No. 08-225904, and Japanese Patent Application No. 08-293490 disclose the use of aluminum in a glass forming mold to provide a self-producing protective layer that is self-generated on the surface of the mold. The chemical wear between the molten glass and the mold surface is prevented by a simple oxide film, and the mold release agent-free operation is achieved by exhibiting mold release properties. This impairs the performance of the mold. That is, it is important to ensure surface characteristics that can withstand repeated mechanical impacts during insertion of the molten glass, particularly high wear resistance.

On the other hand, these alloys are two-phase alloys composed of an Fe phase and a Cu phase, and need to be heated to a high temperature necessary for melting Fe during melting casting. Further, since the solidification temperature of the Fe phase and the solidification temperature of the Cu phase are significantly different, defects are likely to occur during casting. Therefore, for easy melting and casting,
A single-phase alloy having a lower melting temperature than Fe is desirable.
That is, if a single-phase alloy having a lower melting temperature than Fe and capable of developing a self-forming oxide film having a strong protective property on the mold surface can be developed, it is possible to perform molding without applying a release agent.

The present inventors have conducted intensive studies on various single-phase alloys in which an alumina film is formed during high-temperature oxidation, and as a result, by optimizing the components of a Cu-based alloy, a strong protective oxide during high-temperature oxidation is obtained. It was found that a film was formed, and an optimum alloy composition was established.

In the aluminum bronze-based alloy and general aluminum bronze disclosed in Japanese Patent Publication No. 59-502111 and Japanese Patent Application Laid-Open No. 2-228441, an oxide film containing alumina is formed by heat treatment. Since it is not a strong oxide film, the releasability and abrasion resistance at the time of glass molding are remarkably inferior. On the other hand, the present inventors have found that an alloy mainly composed of Cu—Al does not contain Zn or Mn which deteriorates an oxide film, and one or more rare earth elements are indispensable. By adding the generated Zr, we succeeded in developing an alloy for molds with unprecedented superior characteristics. Further, in consideration of the high-temperature strength and the like when used as a glass mold, an alloy that does not harm the durability of the film is added to obtain an alloy that satisfies all the requirements as a glass mold.

Next, the reasons for limiting the composition of the alloy of the present invention will be described. [Al: 4% or more and less than 12%] Al forms an alumina film on the surface of a mold, exhibits releasability, and generates a hard phase containing an intermetallic compound to increase high-temperature strength. It is an important element. To form an alumina film on the mold surface by heating in an oxidizing atmosphere, the amount of Al is 3
% Or more is required. However, at 12% or more, β
It is not preferable because the phase is crystallized and becomes extremely brittle. On the other hand, since a part of the added amount is consumed to generate a hard phase containing an intermetallic compound at the time of casting, the content is set to 4% or more and less than 12%.

[Ni: 10% or more and less than 25%]
NiAl is an element for increasing the high-temperature strength by generating an intermetallic compound of NiAl. For this purpose, 10% or more is required, and at 25% or more, the effect is saturated.

[Fe: less than 8%] Fe does not contribute to the durability of the film, but is an element for increasing the high-temperature strength. Therefore, when high temperature strength is required, it is desirable to add it. However, if the content is 8% or more, defects are likely to occur during casting, so the content is set to less than 8%.

[Si: less than 4%] Like Fe, Si is an element for increasing high-temperature strength. Therefore,
If high-temperature strength is required, it is desirable to add it. However, when the content is 4% or more, the durability of the film is deteriorated, so that the content is set to less than 4%.

[One or more rare earth elements: 0.1.
02% or more and less than 1.0%] Rare earth elements such as Ce and La have the effect of stabilizing the oxide film, and in particular, enhancing the peeling resistance and preventing the peeling of the film due to mechanical and thermal shocks. . For this purpose, 0.02% or more is required.
On the other hand, if it is 0% or more, the thermal fatigue strength of the alumina film at a high temperature is undesirably reduced.

[Zr: 0.05% or more and less than 0.8%] Z
r is selectively oxidized similarly to Al during high-temperature oxidation, and forms a strong protective oxide film on the surface. To do this,
0.05% or more is necessary, and 0.8% or more is not preferable because the oxide film is easily peeled off.

Next, a mold using the alloy of the present invention will be described. As described above, alloys used as glass molding dies are required to have good thermal conductivity and high high-temperature hardness. However, since the heating and cooling states differ depending on the mold part, measures such as adding a cooling fin or using a material having various heat conductions to balance the heat are generally taken. Also, if Ni is added to ensure high-temperature hardness, the grinding efficiency during die processing is reduced, so it is desirable not to use Ni in unnecessary parts. In the alloy of the present invention, heat conduction can be controlled mainly by the amount of Cu, and high-temperature hardness can be controlled by the amount of Ni. Therefore, in consideration of these facts, a mold made of the alloy of the present invention having appropriate heat conduction and high-temperature hardness in each part and generating an oxide film by heating in an oxidizing atmosphere has an unprecedented abrasion resistance. It is a mold that has the properties and does not require the release agent application work, and has the performance that can be used continuously for a long time.

In order to form a strong oxide film, it is necessary to heat in an oxidizing atmosphere at a temperature of 800 ° C. or more for 1 hour or more. Usually, in the low temperature range during heating, C along with Al and Zr
Oxides that are not protective and easily peel off, such as u and Ni, are also generated. However, in a high temperature range of 800 ° C. or more, A gradually increases.
It changes only to oxides of l and Zr, and forms a strong protective oxide film. Therefore, at temperatures below 800 ° C., Cu, Ni
Since oxides that easily peel off remain, the strength of the film deteriorates, which is not preferable. For heating for less than 1 hour, A
It is not preferable because changes of l and Zr to oxides are not sufficient.

[0022]

EXAMPLES The present invention will be further described below with reference to examples. Example 1 An alloy of the present invention and a comparative material having the compositions shown in Table 1 were melted in an induction heating furnace to prepare a cylindrical ingot having a diameter of 200 mm and a height of 400 mm. From the bottom side, make the ingot 10
The specimen cut to a height of 0 mm was used as a test material for a wear resistance test. 35mm capacity from remaining 300mm height material by machining
A 0 cc small mold for beer bottle molding (coarse mold for parison molding) was prepared. Further, this mold was subjected to a film forming treatment at 900 ° C. × 5 hours in the air using an electric furnace to obtain a mold for a molding test.

[0023]

[Table 1]

A 50 mm square ×
A 5 mm block was cut out, polished in one direction with No. 600 emery paper, and subjected to a film formation treatment at 900 ° C. × 5 hours. Using this test piece, the wear resistance of the oxide film was measured by a wear tester. The measurement was performed while pressing the roller with 1000 emery paper wound with a load of 3 kg.
The change in frictional resistance was observed by reciprocating cycles. The result is shown in FIG.

When the oxide film is present on the entire surface, the hardness of the surface is high and the frictional resistance is small, but the hardness decreases as the metal surface is exposed due to wear, so that the frictional resistance increases. Therefore, the quality of wear resistance can be determined based on the difference in the change in the frictional resistance from an initial low state to a high and constant. From FIG. 1, it can be seen that the alloy of the present invention has an oxide film that lasts up to a high cycle and has extremely excellent wear resistance as compared with the comparative material.

Example 2 Using a mold (coarse mold) manufactured as described above for the alloy of the present invention and the comparative material, the single weight of the molten glass was 160
g, a molding speed of 10 times / min, and a glass bottle molding was carried out under the condition that no release agent was applied. In the mold manufactured from the comparative material, the glass was seized after several moldings, and it was impossible to continue molding. On the other hand, it did not occur at all in the alloy of the present invention. In addition, as a result of observing the state of the inner surface of the mold after use, none of the alloys of the present invention caused roughening of the mold surface, and thus a long-time non-coating operation capable of collecting a product having good surface properties was realized. .

[0027]

According to the metal mold for glass forming of the present invention, the oxide film formed has high abrasion resistance, and there is no wear of the oxide film on the mold surface due to the mechanical impact of the molten glass. Time release agent-free operation becomes possible. Thereby, the improvement of the product quality and the operation yield are greatly improved, and an extremely large effect is obtained.

[Brief description of the drawings]

FIG. 1 shows the results of a wear resistance test of an oxide film of an alloy of the present invention and a comparative material.

Claims (7)

[Claims] (1) an Al content of at least 4% and less than 12%;
i 10% or more and less than 25%, one or two rare earth elements
Kind Code: A1 An alloy for a glass molding die, comprising at least 0.02% to less than 1.0%, less than 8% Fe, and less than 4% Si, with the balance being Cu and inevitable elements. 2. The composition according to claim 1, wherein the weight ratio of Al is at least 4% and less than 12%
i 10% or more and less than 25%, one or two rare earth elements
Seed or more 0.02% or more and less than 1.0%, Zr 0.05
% Or less, less than 0.8%, less than 8% Fe, and less than 4% Si, the balance being Cu and unavoidable elements. 3. A mold for glass molding, comprising a mold comprising the alloy according to claim 1 and 2 having a strong oxide film on the surface. 4. The glass molding die according to claim 3, wherein the oxide film is an oxide of Al and Zr. 5. A mother alloy is melted and cast to produce an alloy for a glass molding die, which is machined into a die, and the die is kept at a temperature of 800 ° C. or more for one hour or more. And producing a strong oxide film on the surface. 6. An alloy for a glass molding die, wherein the weight ratio is Al
4% or more and less than 12%, Ni 10% or more and less than 25%,
One or more rare earth elements 0.02% or more
The method for producing a glass molding die according to claim 5, characterized in that it contains less than 0%, less than 8% Fe, and less than 4% Si, with the balance being Cu and unavoidable elements. 7. The glass molding die alloy is made of Al in weight ratio.
4% or more and less than 12%, Ni 10% or more and less than 25%,
One or more rare earth elements 0.02% or more
0%, Zr 0.05% or more and less than 0.8%, Fe
The method for producing a glass molding die according to claim 5, characterized in that it contains less than 8% and less than 4% of Si, and the balance consists of Cu and inevitable elements.