JP6273608B2 - Low melting point alloy recovery method - Google Patents

Description

The present invention relates to a method for recovering a low melting point alloy.

It is known that a low-melting-point alloy is used as a core in resin molding as disclosed in Patent Document 1. In this case, the low-melting-point alloy core is eluted by high-frequency heating or heating with a heat medium, and then a high-pressure / high-temperature liquid is injected into the molded product to remove and recover the low-melting-point alloy.
On the other hand, the low melting point alloy may be used as a chucking material for complicated shaped parts such as turbine blades and jet engine parts. Furthermore, when fixing complicated shaped parts, casting stress is integrated with a low melting point alloy to prevent tightening stress deformation and thermal deformation.
However, after forming, a complicated shaped part is taken out by cutting, and the cutting waste is discarded in a mixed state of a low melting point alloy and a metal part.

  However, low melting point alloys are expensive and are desirably recovered and reused.

Japanese Patent Laid-Open No. 2-167707

  Therefore, an object of the present invention is to reduce the manufacturing cost by recovering and using the low melting point alloy from the mixture (mixed liquid) of the metal microscopic object and the low melting point alloy exemplified by the above-mentioned cutting scraps. It is to be able to plan.

  The present invention that has solved the above problems is as follows.

<Invention of Claim 1>
From a mixture of a low melting point alloy containing at least one selected from the group consisting of bismuth, tin, lead, indium, cadmium, and antimony and melting in a temperature range of 16 ° C. to 183 ° C., and a metal body, the low melting point the alloy was separated, a method for recovering the low-melting alloy,
The mixture of the metal body and the low-melting-point alloy is stirred in oil, heated by raising the oil temperature to be higher than the melting temperature of the low-melting-point alloy, and then cooled to cool the metal body and the low-melting-point alloy. And recovering the low melting point alloy by separating and recovering the low melting point alloy.

< Other inventions>
A method of recovering a low melting point alloy by separating a low melting point alloy selected from the group consisting of bismuth, tin, lead, indium, cadmium and antimony and melting at a temperature range of 16 ° C. to 183 ° C. Because
In a state where the oil temperature in the container is raised to a temperature higher than the melting temperature of the low melting point alloy and heated, the liquid mixture of the metal microparticles and the low melting point alloy is stirred in the oil, and then the metal mixture is stirred from the stirring liquid mixture. A method for recovering a low-melting-point alloy, comprising: separating and recovering a low-melting-point alloy by filtering and separating a minute body.

< Other inventions>
When filtering and separating the metal fine bodies from the stirred mixed liquid, the filter medium provided in the container is passed while applying pressure to the stirred mixed liquid to capture the metal fine bodies in the filter medium, and A method for recovering a low-melting-point alloy in which the melting-point alloy is separated and recovered as a flow-through.

< Other inventions>
When filtering and separating the metal microparticles from the stirred mixed solution, a permeation mesh is sequentially reduced in the container to provide filter media in multiple stages, the stirred mixed solution is sequentially passed through the filter media group, and the metal is passed through the filter media. A method for recovering a low-melting-point alloy, which captures a minute body and separates and recovers the low-melting-point alloy as a liquid passing material.

< Other inventions>
An apparatus for separating a low melting point alloy selected from the group consisting of bismuth, tin, lead, indium, cadmium and antimony and melting at a temperature range of 16 ° C. to 183 ° C. Because
A container for storing a mixture of the metal fine body and the low melting point alloy, an oil addition means for adding oil into the container, and a mixed liquid of the metal micro body and the low melting point alloy in the oil are heated. A heating means, a stirring means for stirring the mixed liquid, and a solid-liquid separation means for filtering and separating the metal microparticles from the stirred mixed liquid;
An apparatus for recovering a low melting point alloy, comprising:

  According to the present invention, it is possible to reduce the manufacturing cost by recovering and using the low melting point alloy from the mixture (mixed liquid) of the metal fine body and the low melting point alloy.

1 is a schematic explanatory diagram of a first embodiment according to the present invention. It is an illustration explanatory drawing of the operation flow of 1st Embodiment. It is outline | summary explanatory drawing of 2nd Embodiment which concerns on this invention. It is an illustration explanatory drawing of the operation flow of 2nd Embodiment.

  Hereinafter, embodiments of the present invention will be described in detail.

[About low melting point alloys]
The object of the present invention is to recover a low melting point alloy which is selected from the group consisting of bismuth, tin, lead, indium, cadmium and antimony and which melts in a temperature range of 16 ° C to 183 ° C. In particular, it is a low melting point alloy mainly composed of bismuth and tin and, if necessary, indium added.
A typical example of this type of low melting point alloy is the “U Alloy” series manufactured by Osaka Asahi Metal Factory. Many melting points are sold in the range of 16 ° C to 183 ° C.
When performing separation from the metal microparticle according to the present invention, a low melting point alloy having a melting point in the range of 90 ° C. to 150 ° C. can be particularly targeted.

[Outline of collection method]
The present invention is a method for recovering a low melting point alloy obtained by mixing metal fines in a low melting point alloy, for example, separating from the above-mentioned cutting waste. The metal constituting the “metal microbody” is not limited. The form of the “microscopic object” is not limited to a powder form or a particle form, but a linear form or a lump form. Typically, it is in the form of chips by a cutting tool.

In the present invention, the mixture of the metal fine body and the low melting point alloy is put into a container, and then oil is added, or the mixture is put into a container in which oil has been put in advance.
Thus, the mixture is stirred in oil, and the oil temperature is raised to the melting temperature of the low melting point alloy or higher.

  Then, it cools and solid-liquid-separates a metal microbody and a low melting-point alloy using a sieve simply, and separates and collects a low melting-point alloy.

In the present invention, oils such as vegetable oils, mineral oils and synthetic oils are used. When the oil is not used, the metal microparticles remain scattered in the low melting point alloy dissolved, but when the oil is used, the reason is not clear, but the metal microparticles tend to aggregate. In the solid-liquid separation such as sieving, the separability between the metal fine body and the low melting point alloy is enhanced.
Furthermore, when oil is not used, the low melting point alloy adheres to the inner wall of the container or adheres to the mesh during solid-liquid separation, causing clogging and lowering the recovery efficiency. The liquid repellency increases as the contact angle of the low melting point alloy increases, so that the adhesion to the inner wall of the container and the adhesion to the solid-liquid separation material can be prevented, and the collection can be performed with a high recovery rate. It is also desirable for maintenance.
On the other hand, heating is necessary for melting the low melting point alloy, but oxidation cannot be avoided by applying a fire. When using water, if the melting temperature is high, it is not suitable for manual work due to steam. In response to these problems, when oil is used, the low melting point alloy can be easily melted at a high temperature in a non-oxidized state.

  In the present invention, the stirring operation into the oil of the mixture of the metal microparticles and the low melting point alloy, the heating operation for raising the oil temperature to be higher than the melting temperature of the low melting point alloy, the temporal relationship of the work within each operation, In addition, it should be noted that the temporal relationship between each operation is not questioned.

[First Embodiment]
In carrying out the present invention, separation and collection can be carried out using a physics and chemistry experimental instrument. However, in the case of a large amount of treatment, separation and collection can be carried out by the apparatus shown in FIG. 1, for example.
As a low melting point alloy recovery device according to the first embodiment, a container 10 for storing a mixture M of metal fine bodies and the low melting point alloy, an oil adding means 12 for adding oil 11 into the container 10, Heating means for heating the mixed liquid of the metal microparticles and the low-melting-point alloy in the oil 11, a stirring means 14 for stirring the mixed liquid, and a solid body for filtering and separating the metal fine bodies from the stirred mixed liquid. Liquid separation means 20.

Under such an apparatus, the mixture M of the metal fine body and the low melting point alloy is put into the container 10, and the oil 11 is also allowed to flow into the heating container 10.
The heating container 10 is provided with stirring means 14 having a motor-driven stirring blade. Furthermore, the heating container 10 is provided with a heater and heating means (not shown) for circulating a heat medium through a jacket provided on the wall of the container 10.

A series of operation sequence examples is shown in FIG. That is, the mixture M with fine metal body and a low-melting alloy were placed into the container 10 (S1), it is heated in the container 10 (S2). The oil 11 is caused to flow (add) into the heating container 10 (S3). Subsequently, the stirring means 14 is operated (S4), and stirring is performed. Stirring may be continuous or intermittent stirring. The stirring speed can be changed over time.

After the stirring is completed, the vibration device 21 is operated (S5), and the liquid of the mixture M after the stirring process is opened (S6) and flows into the filtration container 20 from the container 10. The vibration filtration container 20 has, for example, sieves m1 to m3 that sequentially reduce the sieve mesh, and passes through the sieves m1 to m3 by the dead weight of the liquid of the mixture M and the applied vibration force to perform filtration (S7). In the process, the metal particles are captured by the sieves m1 to m3, and the low melting point alloy is recovered in the recovery container 22 (S8).
The recovered low melting point alloy can be reused.
In addition, the area | region containing the heating container 10 can be cleaned by the dust collector 30 or the smoke collector.

[Second Embodiment]
A second embodiment is shown in FIG. In this embodiment, the pressure filtration container 20 is used.
The operation in this example is shown in FIG. That is, the metal fine body and the low melting point alloy are stirred (S4). Thereafter, at an appropriate time, with the air vent valve 23 of the filtration container 20 opened, the liquid of the mixture M after the stirring process is opened ( S6 ), and the filtration container 20 from the container 10 is opened. Let it flow into. For example, the filtration container 20 includes sieves m1 to m3 that sequentially reduce the sieve mesh. The pressurizing valve 24 is opened to the liquid of the mixture M, the pressure by the compressed air is applied, the sieves m1 to m3 are passed, and filtration is performed ( S10 ). The number of stages of the sieves m1 to m3 and the sieve mesh can be appropriately selected. In the process, the metal particles are captured by the sieves m1 to m3, and the low melting point alloy is recovered in the recovery container 22 ( S11 ).

(Example)
The low melting point alloy ("U alloy-138") manufactured by Osaka Asahi Metal Factory was cast and integrated to form, and the subsequent cutting waste was recovered in the first embodiment and the second embodiment. As a result, it was found that the product can be recovered with a high yield without any problem.

Claims (1)

From a mixture of a low melting point alloy containing at least one selected from the group consisting of bismuth, tin, lead, indium, cadmium, and antimony and melting in a temperature range of 16 ° C. to 183 ° C., and a metal body, the low melting point the alloy was separated, a method for recovering the low-melting alloy,
The mixture of the metal body and the low-melting-point alloy is stirred in oil, heated by raising the oil temperature to be higher than the melting temperature of the low-melting-point alloy, and then cooled to cool the metal body and the low-melting-point alloy. And recovering the low melting point alloy by separating and recovering the low melting point alloy.

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