JP2022094455A - Apparatus and method for evaluating die-cast mold release agent or lubricant - Google Patents

Abstract

To provide an apparatus and method for evaluating a die-cast mold release agent or lubricant that allows for evaluating the releasability from and heat transferability to a metal mold.SOLUTION: An apparatus 10 for evaluating a die-cast mold release agent or lubricant comprises a metal block 1, a cylindrical part 2, a force measuring unit 4 and a temperature measuring unit 5. The metal block 1 has a mold-release surface 1a over which a mold-release agent or lubricant is applied. The cylindrical part 2 is placed on the mold-release surface 1a of the metal block 1 in a manner closing a lower end of the cylindrical part 2. The force measuring unit 4 measures a push-out or pulling force acted upon pushing out or pulling the cylindrical part 2 after forming a solidification piece SL1 by pouring a melt inside the cylindrical part 2 into solidification. The temperature measuring unit 5 measures a temperature at a lower part of the metal block 1 at one of time points of from forming the solidification piece SL1 to pushing out or pulling the cylindrical part 2.SELECTED DRAWING: Figure 1

Description

The present invention relates to an evaluation device and an evaluation method for a die casting mold release agent or a lubricant.

An example of such a die casting mold release agent or lubricant evaluation device is disclosed in Patent Document 1. In the die casting mold release agent or lubricant evaluation device disclosed in Patent Document 1, the mold release agent or lubricant is applied to the flat surface portion of the heated metal block, and the metal block is closed so as to close the lower end portion of the tubular metal block. Place in. The molten aluminum is poured into a metal block, and the molten aluminum is actually solidified to form an aluminum casting. After the molten aluminum solidifies, the metal block is pulled, and the tensile force when the metal block and the aluminum casting inside the metal block start to move on the flat surface portion of the metal block is measured. The mold release property of the mold release agent or the lubricant is evaluated based on the measured value of the tensile force.

Japanese Unexamined Patent Publication No. 2005-009971

The inventors of the present application have discovered the following problems.
The mold release agent or lubricant has, for example, heat transferability from the mold release agent or lubricant to the mold, except for the mold release property. With such a die casting mold release agent or lubricant evaluation device, the heat transferability from the mold release agent or lubricant to the mold could not be evaluated.

In view of the above-mentioned problems, an object of the present invention is to provide an evaluation device and an evaluation method for a die-cast mold release agent or a lubricant capable of evaluating a mold release property and a heat transfer property to a mold.

The die casting mold release agent or lubricant evaluation device according to the present invention is
With a metal block,
Cylindrical part and
Force measurement unit and
In a die casting mold release agent or lubricant evaluation device including a temperature measuring unit.
The metal block has a mold release surface coated with a mold release agent or a lubricant.
The tubular portion is placed on the release surface of the metal block so as to close the lower end portion of the tubular portion.
The force measuring unit pours the molten metal into the inside of the tubular portion to solidify it to form a solidified piece, and then measures the pushing force or the pulling force when the tubular portion is pushed out or pulled.
The temperature measuring unit measures the temperature of the lower part of the metal block at one time point from the time when the coagulated piece is formed to the time when the tubular part is extruded or pulled.

With such a configuration, the heat transferability to the mold can be evaluated based on the temperature of the lower part of the metal block. In addition, the mold release property of the die casting mold release agent or the lubricant can be evaluated based on the pushing force or the pulling force. Therefore, the mold releasability and the heat transferability to the mold can be evaluated.

Further, the temperature measuring unit may be characterized by including a thermoelectric element in contact with the lower part of the metal block and a cooling block in contact with the thermoelectric element.

With such a configuration, the temperature of a predetermined region below the metal block can be measured. Therefore, the heat transferability to the mold can be evaluated with good accuracy.

Further, the cooling block may be cooled so that the temperature difference between the metal block and the cooling block is 50 ° C. or higher.

According to such a configuration, since the temperature difference between the metal block and the cooling block is sufficient, the electric power generated by the thermoelectric element is increased. Therefore, the temperature of the lower part of the metal block can be stably measured.

Further, the method for evaluating the die casting mold release agent or the lubricant according to the present invention is as follows.
A mold release agent or a lubricant is applied to the mold release surface of the metal block, the tubular portion is placed on the mold release surface of the metal block so as to close the lower end portion of the tubular portion, and the molten metal is placed in the tubular shape. A step of measuring the pushing force or pulling force when the tubular part is pushed out or pulled after being poured into the inside of the portion and solidified to form a solidified piece.
It comprises a step of measuring the temperature of the lower part of the metal block at one time point from the time when the solidified piece is formed to the time when the tubular portion is extruded or pulled.

With such a configuration, the heat transferability to the mold can be evaluated based on the temperature of the lower part of the metal block. In addition, the mold release property of the die casting mold release agent or the lubricant can be evaluated based on the pushing force or the pulling force. Therefore, the mold releasability and the heat transferability to the mold can be evaluated.

Further, in the step of measuring the temperature of the lower part of the metal block at one time point from the time when the solidified piece is formed to the time when the tubular portion is extruded or pulled.
The thermoelectric element is in contact with the lower part of the metal block, and the cooling block is cooled so that the temperature difference between the lower part of the metal block and the cooling block is 50 ° C. or more while the cooling block is in contact with the thermoelectric element. It may be characterized by doing.

According to such a configuration, since the temperature difference between the metal block and the cooling block is sufficient, the electric power generated by the thermoelectric element is increased. Therefore, the temperature of the lower part of the metal block can be stably measured.

The present invention can provide an evaluation device and an evaluation method for a die-cast mold release agent or a lubricant capable of evaluating a mold release property and a heat transfer property to a mold.

It is a schematic diagram which shows the evaluation apparatus which concerns on Embodiment 1. FIG. It is a flowchart which shows the evaluation method of the mold release agent using the evaluation apparatus which concerns on Embodiment 1. FIG. It is a schematic diagram which shows the main part of the specific example of the evaluation apparatus which concerns on Embodiment 1. FIG. It is a partial cut-out sectional view which shows the main part of the specific example of the evaluation apparatus which concerns on Embodiment 1. FIG. It is a partial cut-out sectional view which shows the main part of another specific example of the evaluation apparatus which concerns on Embodiment 1. FIG. It is a partial cut-out sectional view which shows the main part of another specific example of the evaluation apparatus which concerns on Embodiment 1. FIG. It is a graph which shows the tensile force with respect to the generated voltage. It is a photograph which shows the bottom surface of an example of a solidified piece.

Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. Further, in order to clarify the explanation, the following description and drawings are appropriately simplified.

(Embodiment 1)
The first embodiment will be described with reference to FIG. As a matter of course, the right-handed XYZ coordinates shown in FIG. 1 and other drawings are for convenience to explain the positional relationship of the components. Normally, the Z-axis plus direction is vertically upward, and the XY plane is a horizontal plane, which is common between drawings.

As shown in FIG. 1, the evaluation device 10 includes a metal block 1, a tubular portion 2, a hot water supply guide 3, a tensile force measuring device 4, and a temperature measuring unit 5.

The metal block 1 is a block body made of a metal material. As such a metal material, for example, a material for die casting dies, which is expected to use a mold release agent, can be used. The metal block 1 has main surfaces 1a and 1b. The main surface 1a may be a plane facing upward (here, the Z-axis plus side). The main surface 1a may be referred to as a release surface. The main surface 1b may be a plane facing downward (here, the negative side of the Z axis).

The tubular portion 2 is, for example, a cylindrical body. An eyebolt 4a is fastened to the outer peripheral surface of the tubular portion 2. A tensile force measuring device 4 is mechanically connected to the tubular portion 2 via an eyebolt 4a.

The hot water supply guide 3 is a tubular body and includes an inlet 3a and an outlet 3b. The diameter of the outlet 3b is smaller than that of the inlet 3a. The hot water supply guide 3 is provided so as to be able to be arranged above the tubular portion 2.

The tensile force measuring device 4 includes, for example, a drive source (not shown) and a force sensor. The force sensor is, for example, a load cell. The drive source pulls the cylindrical portion 2 via the force sensor and the eyebolt 4a. The force sensor receives pressure and produces a signal indicating a tensile force.

The temperature measuring unit 5 is provided on the lower side of the metal block 1. Further, when the temperature measuring unit 5 is located below the tubular portion 2, the temperature of the portion of the metal block 1 may be measured at a position close to the solidified piece SL1. The temperature measuring unit 5 may be any one that measures a signal indicating a temperature or a temperature difference, and is, for example, a thermocouple, a thermoelectric element, or the like. The temperature measuring unit 5 may be appropriately provided with a processing device that amplifies a signal indicating a temperature or a temperature difference.

(Evaluation method)
Next, a method for evaluating the release agent will be described with reference to FIG. FIG. 2 is a flowchart showing a method of evaluating a mold release agent using the evaluation device 10 shown in FIG.

The main surface 1a of the metal block 1 is coated with the release agent (release agent application step ST1). A film made of a mold release agent is formed on the main surface 1a of the metal block 1. The coating conditions, for example, the coating method, the temperature of the metal block 1, and the like may be set to the same conditions as the mold release agent and the mold used in die casting. For example, the mold release agent may be applied to the main surface 1a using a spray, or the temperature of the metal block 1 may be adjusted in the same manner as the temperature of the mold. Further, the temperature measurement of the lower part of the metal block 1 may be started before the start of this step. The lower portion of the metal block 1 may be a portion of the metal block 1 located below the main surface 1a.

Subsequently, the tubular portion 2 is placed on the main surface 1a of the metal block 1 (cylindrical portion mounting step ST2). The lower end of the tubular portion 2 and the main surface 1a of the metal block 1 are closed.

Subsequently, the molten metal is passed through the hot water supply guide 3 and poured into the inside of the tubular portion 2 (molten metal supply step ST3). The molten metal is preferably a melted alloy for die casting used in die casting. The alloy for die casting is, for example, an aluminum alloy, a magnesium alloy, or the like. Since the space between the lower end portion of the tubular portion 2 and the main surface 1a of the metal block 1 is closed, the molten metal stays inside the tubular portion 2 and hardly goes out to the outside of the tubular portion 2.

Subsequently, the molten metal is solidified to form the solidified piece SL1 (solidified piece forming step ST4). The metal block 1 and the tubular portion 2 cool the molten metal, and the shapes of the metal block 1 and the tubular portion 2 are transferred to the solidified piece SL1. The metal block 1 and the tubular portion 2 correspond to a die-casting die, and the solidified piece SL1 corresponds to a die-casting casting.

Finally, the tensile force measuring device 4 measures the tensile force while the temperature measuring unit 5 measures the temperature of the lower part of the metal block 1 (temperature and tensile force measuring step ST5). Specifically, the tensile force measuring device 4 may pull the solidified piece SL1 until it separates from the main surface 1a, and measures the tensile force. It is preferable that the tensile force measuring device 4 measures the tensile force while a predetermined load is applied to the solidified piece SL1 by placing a weight on the solidified piece SL1 or the like. The load on the solidified piece SL1 may be set in consideration of the molten metal pressure in die casting. Further, the temperature of the lower part of the metal block 1 may be measured at at least one time point from the time when the solidified piece SL1 is formed to the time when the tubular portion 2 is pulled. The heat transferability from the mold release agent to the mold is evaluated based on the measured value of the temperature at the lower part of the metal block 1. As the measured value of the temperature of the lower part of the metal block 1, the measured value of the temperature of the lower part of the metal block 1 at one time point from the time when the solidified piece SL1 is formed to the time when the tubular portion 2 is pulled is used. May be good.

From the above, the heat transferability to the mold can be evaluated based on the temperature of the lower part of the metal block 1 measured by the temperature measuring unit 5. Further, the mold release property of the die casting mold release agent or the lubricant can be evaluated based on the tensile force measured by the tensile force measuring device 4. Therefore, the mold releasability and the heat transferability to the mold can be evaluated.

(Specific examples)
Next, each specific example of the evaluation device 10 will be described with reference to FIGS. 3 to 6. Each specific example of the evaluation device 10 shown in FIGS. 3 to 6 has the same configuration as each specific example shown in FIG. 1, except for the temperature measuring unit 5.

(First specific example)
A specific example of the evaluation device 10 shown in FIGS. 3 and 4 includes one thermocouple 5a, which is a specific example of the temperature measuring unit 5. One thermocouple 5a is inserted into one hole 1c provided in the main surface 1b of the metal block 1. According to such a configuration, one specific example of the temperature measuring unit 5 shown in FIGS. 3 and 4 measures the temperature of one portion located at the lower part of the metal block 1 and below the solidified piece SL1. , The temperature of the lower part of the metal block 1 can be measured.

(Second specific example)
A specific example of the evaluation device 10 shown in FIG. 5 includes a plurality of thermocouples 5b, which is a specific example of the temperature measuring unit 5. The plurality of thermocouples 5b are inserted into the plurality of holes 1d provided in the main surface 1b of the metal block 1, respectively. According to such a configuration, in one specific example of the evaluation device 10 shown in FIG. 5, the temperature of a plurality of portions located at the lower part of the metal block 1 and below the solidified piece SL1 is measured, and the metal block 1 is measured. The temperature at the bottom of the can be measured.

By the way, as shown in FIG. 8, there is a solidified piece SL2 which is a specific example of the solidified piece SL1. The solidified piece SL2 is formed by solidifying a molten metal made of an aluminum alloy. Gas pools SL2b, SL2b, SL2b, SL2b, and SL2b were confirmed on the lower surface SL2a of the solidified piece SL2. In each of the gas pools SL2b, it is presumed that the gas generated from the mold release agent is accumulated in the lower surface SL2a of the solidified piece SL2. The gas pool SL2b and the portion corresponding to the main surface 1a of the metal block 1 do not come into contact with each other because there is a cavity due to the gas pool SL2b.

A specific example of the temperature measuring unit 5 shown in FIG. 5 has more parts for measuring the temperature than the specific example of the temperature measuring unit 5 shown in FIGS. 3 and 4. Therefore, when a large amount of gas pools are generated on the lower surface of the solidified piece as in the solidified piece SL2, one specific example of the temperature measuring unit 5 shown in FIG. 5 is the temperature measuring unit 5 shown in FIGS. 3 and 4. Compared with one specific example, the temperature of the lower part of the metal block 1 can be measured with good accuracy.

(Third specific example)
A specific example of the evaluation device 10 shown in FIG. 6 includes a thermoelectric element 5c, which is a specific example of the temperature measuring unit 5, and a cooling block 6.

The thermoelectric element 5c is, for example, a Zeebeck element. The thermoelectric element 5c is connected to an electric circuit including a voltmeter and the like.

The cooling block 6 includes a main body 6a and a flow path 6b. The main body 6a may be provided so as to be thermally conductive with the thermoelectric element 5c. The main body 6a is provided so as to be in close contact with the thermoelectric element 5c, for example. The flow path 6b is connected so as to supply and discharge a cooling medium to a cooling device (not shown). The cooling device cools the cooling medium and supplies the cooling medium to the flow path 6b. The cooling medium takes heat from the main body 6a in the flow path 6b, and then is discharged from the flow path 6b and returns to the cooling device. By continuously performing these, the cooling block 6 can be cooled and the thermoelectric element 5c can be cooled.

The thermoelectric element 5c generates a voltage according to the temperature difference between the metal block 1 and the cooling block 6. When the temperature difference between the metal block 1 and the cooling block 6 is 50 ° C. or higher, the thermoelectric element 5c generates a voltage having a sufficient magnitude, which is preferable. The cooling block 6 may be cooled so as to be 50 ° C. or lower than the temperature of the metal block 1. The voltage generated by the thermoelectric element 5c can be measured using a voltmeter or the like, and the temperature of the lower part of the metal block 1 can be calculated based on the measured voltage.

Further, one specific example of the evaluation device 10 shown in FIG. 6 can measure the temperature of a predetermined region on the lower surface of the solidified piece SL1. Therefore, one specific example of the evaluation device 10 shown in FIG. 6 directly measures the temperature of a predetermined region itself on the lower surface of the solidified piece SL1 as compared with one specific example of the evaluation device 10 shown in FIGS. 3 to 5. can do. Since it is not necessary to provide holes 1c and 1d in the lower portion of the metal block 1 in the specific example of the evaluation device 10 shown in FIG. 6, the metal block is compared with the specific example of the evaluation device 10 shown in FIGS. 3 to 5. The heat transfer in 1 is stable. As a result, the specific example of the evaluation device 10 shown in FIG. 6 can measure the temperature of the lower part of the metal block 1 with good accuracy as compared with the specific example of the evaluation device 10 shown in FIGS. 3 to 5. can.

(Example of evaluation result)
Next, with reference to FIG. 7, an example of the evaluation result of the release agent using the above-mentioned evaluation method will be described.

In the evaluation method described above, a specific example of the evaluation device 10 shown in FIG. 6 was used. In the above-mentioned evaluation method, a total of three types of oil-based mold release agents L1, L2, and L3 were evaluated. The application conditions of the mold release agent, the temperature conditions of the metal block, etc. are common. The tensile force and the generated voltage were measured, and the results are shown in FIG. This measured tensile force corresponds to the mold release resistance force.

As shown in FIG. 7, the measured value of the tensile force of the oil-based mold release agent L1 and the measured value of the tensile force of the oil-based mold release agent L2 are substantially the same value. Therefore, the film with the oil-based mold release agent L2 has the same degree of releasability as the film with the oil-based mold release agent L1, and is good.

On the other hand, as shown in FIG. 7, the measured value of the generated voltage of the oil-based mold release agent L2 is higher than the measured value of the generated voltage of the oil-based mold release agent L1. Therefore, the film made of the oil-based mold release agent L2 is superior in heat transfer to the mold as compared with the film made of the oil-based release agent L1. Therefore, it is considered that the thickness of the film due to the oil-based release agent L2 is thinner than the thickness of the film due to the oil-based release agent L1. From the above, it is presumed that the oil-based mold release agent L2 is superior to the oil-based mold release agent L1 in actual casting because it has the same level of mold release property but is excellent in heat transfer to the mold. To.

As shown in FIG. 7, the measured value of the tensile force of the oil-based mold release agent L3 is higher than the measured value of the tensile force of the oil-based mold release agents L1 and L2. Therefore, the film made of the oil-based mold release agent L3 has a lower releasability than the film made of the oil-based release agents L1 and L2, and is poor.

Further, as shown in FIG. 7, the measured value of the generated voltage of the oil-based mold release agent L3 is higher than the measured value of the generated voltage of the oil-based mold release agents L1 and L2. Therefore, it is considered that the thickness of the film due to the oil-based release agent L3 is thinner than the thickness of the film due to the oil-based release agents L1 and L2.

Here, the releasability is affected not only by the performance of the film itself by the release agent, but also by the thickness of the film. One of the reasons why the release property of the film by the oil release agent L3 was low is considered to be that the thickness of the film by the oil release agent L3 is too thin, not the performance of the film itself by the oil release agent L3. When the film thickness of the oil-based mold release agent L3 is too thin, it is considered that the oil-based mold release agent L3 has a big problem in coatability. Therefore, by optimizing the application conditions and the like of the oil-based mold release agent L3, the thickness of the film by the oil-based mold release agent L3 is increased, and as a result, sufficient releasability is provided for the film by the oil-based mold release agent L3. It is conceivable that it can be granted.

The present invention is not limited to the above embodiment, and can be appropriately modified without departing from the spirit. Further, the present invention may be carried out by appropriately combining the above-described embodiments and examples thereof. For example, in the above-described first embodiment and its modifications, the release agent is the evaluation target, but the lubricant may be the evaluation target. Further, in the above-described first embodiment and its modified examples, the evaluation device 10 includes a tensile force measuring device 4, but in the above-described first embodiment and its modified examples, the evaluation device 10 includes a force measuring unit. For example, a push output measuring device may be provided.

10 Evaluation device 1 Metal block 1a Main surface (release surface) 1b Main surface 1c, 1d Hole 2 Cylindrical part
3 Hot water supply guide 3a Inlet 3b Outlet 4 Tensile force measuring device 5 Temperature measuring unit 5a, 5b Thermocouple 5c Thermoelectric element 6 Cooling block 6a Main body 6b Flow path SL1, SL2 Coagulant piece ST1 Demolding agent application step ST2 Cylindrical part mounting step ST3 molten metal supply step ST4 solidification piece formation step ST5 temperature and tensile force measurement step

Claims (5)

With a metal block,
Cylindrical part and
Force measurement unit and
In a die casting mold release agent or lubricant evaluation device including a temperature measuring unit.
The metal block has a mold release surface coated with a mold release agent or a lubricant.
The tubular portion is placed on the release surface of the metal block so as to close the lower end portion of the tubular portion.
The force measuring unit pours the molten metal into the inside of the tubular portion to solidify it to form a solidified piece, and then measures the pushing force or the pulling force when the tubular portion is pushed out or pulled.
The temperature measuring unit measures the temperature of the lower part of the metal block at one time point from the time when the coagulated piece is formed to the time when the tubular part is extruded or pulled.
Die-cast mold release agent or lubricant evaluation device. The temperature measuring unit includes a thermoelectric element that comes into contact with the lower part of the metal block and a cooling block that comes into contact with the thermoelectric element.
The die casting mold release agent or lubricant evaluation device according to claim 1. The cooling block is cooled so that the temperature difference between the metal block and the cooling block is 50 ° C. or higher.
The die casting mold release agent or lubricant evaluation device according to claim 2. A mold release agent or a lubricant is applied to the mold release surface of the metal block, the tubular portion is placed on the mold release surface of the metal block so as to close the lower end portion of the tubular portion, and the molten metal is placed in the tubular shape. A step of measuring the pushing force or pulling force when the tubular part is pushed out or pulled after being poured into the inside of the portion and solidified to form a solidified piece.
The step comprises measuring the temperature of the lower part of the metal block at one time point from the time when the solidified piece is formed to the time when the tubular portion is extruded or pulled.
Evaluation method of die casting mold release agent or lubricant. In the step of measuring the temperature of the lower part of the metal block at one time point from the time when the solidified piece is formed to the time when the tubular portion is extruded or pulled.
The thermoelectric element is in contact with the lower part of the metal block, and the cooling block is cooled so that the temperature difference between the lower part of the metal block and the cooling block is 50 ° C. or more while the cooling block is in contact with the thermoelectric element. do,
The method for evaluating a die casting mold release agent or a lubricant according to claim 4.

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