JP7371864B2 - Blister testing machine and blister testing method - Google Patents

Description

The present invention relates to a blister testing machine and a blister testing method.

BACKGROUND ART It has been known that cavities are formed in die castings and other castings by entraining air, decomposed gas from a mold release agent, etc. during the casting process. A cavity is a cavity that occurs inside a casting, and a casting in which a cavity is formed becomes a defective product.

Blast holes can be inspected by heating the casting. When a casting with cavities is heated, bubbles (blister) appear on the surface of the casting, so the presence or absence of blisters can be used to determine whether or not cavities are present. A blister tester is known as a device that performs this (for example, see Patent Document 1).

In this type of blister testing machine, molten salt is placed in a heating pot, a casting such as a die cast is immersed in the pot, and the casting is heated. Heat the casting to a temperature that can cause blisters, and check for blisters.

Jito No. 3009463 Publication

By the way, in the blister tester described in Patent Document 1, the temperature of the casting is increased by immersing the casting in molten salt, but since handling and managing the molten salt is time-consuming, a heater is used to increase the temperature of the casting. It is being considered that the castings can be heated using

In order to use a heater to heat a casting to a temperature that can cause blisters in a short time, the heater needs to be driven at high output. However, if the heater is driven at a high output, the temperature of the casting will rise at a steep slope, and the temperature will tend to overshoot with respect to the target temperature, which may affect the occurrence of blisters.

The present invention has been made in view of the above circumstances, and provides a blister testing machine and a blister testing method that can quickly heat a test specimen to a set temperature in order to shorten measurement time and suppress the overshoot that occurs as a result. The purpose is to

A blister tester according to one aspect of the present invention includes a test specimen holder that holds a test specimen, a heater that heats the test specimen to a set temperature that is set lower than the melting point of the test specimen, and a It includes a temperature sensor for sensing, a cooling device for sending gas to the test object, and a control device for controlling the cooling device. The control device controls the cooling device to send gas to the test specimen when the detection result obtained from the temperature sensor increases in response to heating by the heater and becomes equal to or higher than a preset threshold.

A blister testing method according to one embodiment of the present invention is a blister testing method in which the test specimen is heated to a set temperature that is set below the melting point of the test specimen, and blisters appearing on the test specimen are evaluated. When the temperature of the test body rises as a result of heating the test body and the temperature of the test body exceeds a predetermined temperature value, cooling gas is sent to the test body.

The blister testing machine and blister testing method of the above aspects according to the present invention have the advantage that the test specimen can be quickly heated to the set temperature in order to shorten the measurement time, and the overshoot that occurs accompanying this can be suppressed. .

FIG. 1 is a schematic cross-sectional view of a blister testing machine according to an embodiment of the present invention. FIG. 2 is a block diagram of the control device of the blister testing machine same as above. FIG. 3 is a flowchart illustrating the operation of the blister testing machine mentioned above. FIG. 4 is a graph showing the relationship between heating time and workpiece temperature in Examples and Comparative Examples. FIGS. 5A and 5B are flowcharts illustrating the operation of the blister testing machine according to the modified example.

(1) Embodiment (1.1) Overall The blister testing machine 1 according to the present embodiment will be described in detail below.

The blister tester 1 is a device for carrying out the blister test method, and heats the test specimen X1 to a temperature higher than its softening point. The test piece X1 heated above its softening point develops blistering, such as bubbling, depending on the amount of gas contained in the test piece X1. In the blister test method, the test specimen X1 can be inspected by evaluating the state of occurrence of this bulge visually or by image recognition technology.

"Test object X1" here means an object to be inspected in the blister test method. The "test body X1" may be, for example, a sample of an actual product, or a part of the material constituting the product. The specimen X1 may be made of, for example, aluminum alloy, aluminum magnesium alloy, zinc, copper, or an alloy that is a combination of at least two of these. In the following, a case will be described in which an aluminum die-cast product made up of the ADC 12 is used as the test specimen X1.

Moreover, the "softening point" means the temperature (softening temperature) at which the test specimen X1 begins to deform due to heating. The "softening point" herein refers to the temperature at which the metal softens due to heating and the gas inside the metal expands, causing the metal to begin to expand. For example, the softening point of an aluminum die-cast product made of ADC12 is 535°C. In addition, the "melting point" as used in this specification means the temperature at which the test specimen X1 melts into a complete liquid state, and it is assumed that the melting point>the softening point.

As shown in FIG. 1, the blister testing machine 1 includes a furnace 2, a specimen holder 3, a plurality of heaters 4, a cooling device 5, a temperature sensor 6 (FIG. 2), and a control device 7. Be prepared.

(1.2) Furnace The furnace 2 is a box-shaped device that houses a test specimen holder 3, a heater 4, and a temperature sensor 6 inside. The furnace 2 includes heat insulating materials 21 and 22 and an opening/closing lid 23. Hereinafter, as the heat insulating materials 21 and 22, the heat insulating material inside the furnace 2 will be called the inner heat insulating material 21, and the heat insulating material on the outside will be called the outer heat insulating material 22.

The inner heat insulating material 21 is a heat insulating material that forms an accommodation space in which the test specimen X1 is accommodated. The material of the inner heat insulating material 21 is not particularly limited, and examples thereof include ceramics, metal, white porcelain, platinum, quartz, and alumina. Examples of ceramics include silica, magnesia, calcia, and the like. The inner heat insulating material 21 includes a bottom wall 211, a peripheral wall 212, and a top wall 213, and is formed in the shape of a box with a bottom. The ceiling wall 213 has an opening 214 that penetrates inside and outside. A test specimen holder 3 is attached to the opening/closing lid 23, and by moving the opening/closing lid 23 upward, the specimen holder 3 can be positioned above the ceiling wall 213 through the opening 214. can. On the other hand, by moving the opening/closing lid 23 downward, the opening 214 can be closed and the test specimen holder 3 can be placed at a predetermined position. Therefore, the user places the test specimen X1 on the test specimen holder 3 with the specimen holder 3 positioned above the ceiling wall 213, and then lowers the opening/closing lid 23. can be stored inside.

The outer heat insulating material 22 covers the outer surface of the inner heat insulating material 21 , and specifically covers at least the bottom wall 211 and the peripheral wall 212 of the inner heat insulating material 21 . By covering the outer surface of the inner insulating material 21 with the outer insulating material 22, the temperature inside the inner insulating material 21 can be maintained. Users can be prevented from coming into contact with it.

The opening/closing lid 23 opens and closes the opening 214 of the top wall 213 of the inner heat insulating material 21 . The opening/closing lid 23 moves in the vertical direction between a first position where the opening 214 is closed and a second position where the opening 214 is opened. The opening/closing lid 23 is moved by, for example, an air cylinder, a hydraulic cylinder, an electric cylinder, a linear actuator, a crane, a hoisting device, or the like. The material of the opening/closing lid 23 is not particularly limited, and examples thereof include ceramics, metal, white porcelain, platinum, quartz, and alumina.

The furnace 2 is formed with an air supply hole 24 for introducing the gas sent from the cooling device 5 into the furnace 2, and an exhaust hole 25 for exhausting the internal gas. The air supply hole 24 penetrates the bottom wall 211 of the inner heat insulating material 21 and the outer heat insulating material 22 covering the bottom wall 211. The exhaust hole 25 penetrates the peripheral wall 212 of the inner heat insulating material 21 and the outer heat insulating material 22 covering the surrounding wall 212. However, in the present invention, there is no particular restriction on the positions where the air supply hole 24 and the exhaust hole 25 are formed.

A cooling device 5, which will be described later, is connected to the air supply hole 24. The cooling device 5 supplies gas into the furnace 2 through the air supply hole 24, and the gas supplied from the cooling device 5 is blown out from the opening inside the furnace 2 in the air supply hole 24 toward the test specimen X1. Thereby, the temperature of the test specimen X1 in a high temperature state can be lowered. This will be explained in detail in "(2) Operation example" below.

(1.3) Test specimen holder The specimen holder 3 holds the specimen X1 in the furnace 2. "Holding" here means maintaining the position of the test specimen X1 within the furnace 2. In addition to maintaining the position of the test piece X1 in the furnace 2 by fixing it with a jig or the like, for example, the position of the test piece X1 in the furnace 2 can be maintained by fitting the test piece The term "hold" here also includes holding the test piece X1 on a flat surface and maintaining the position of the test piece X1 in the furnace 2. The test specimen holder 3 according to this embodiment includes a planar mounting table 31 and a support section 32 that supports the mounting table 31.

The mounting table 31 is a portion on which the test specimen X1 is placed. In this embodiment, the mounting table 31 has a flat plate shape, but in the present invention, it may have a sindrical shape, a spherical shape, a donut shape, a wave surface shape, a container shape, etc., for example. The mounting table 31 has a plurality of through holes penetrating in the thickness direction. This allows infrared rays and gas to pass toward the test specimen X1 placed on the mounting table 31. The mounting table 31 is made of, for example, a net, punched metal, expanded metal, etc., but is preferably made of a net from the viewpoint of transmitting infrared rays as efficiently as possible.

The mounting table 31 is arranged at a position facing the air supply hole 24 of the bottom wall 211, and is arranged at a position where it is easily exposed to the gas coming out from the air supply hole 24. Further, the mounting table 31 is supported by the opening/closing lid 23 by a support portion 32, and is arranged below the opening 214 when the opening/closing lid 23 closes the opening 214. The upper surface (sometimes referred to as a mounting surface) and lower surface of the mounting table 31 are along a horizontal plane.

The support portion 32 is a portion that supports the mounting table 31. The support portion 32 supports the mounting table 31 by suspending the mounting table 31 from the open/close lid 23. However, the support part 32 is not limited to the structure in which the mounting table 31 is suspended from the opening/closing lid 23, and the mounting table 31 may be suspended from the top wall 213. The mounting table 31 may be provided at the upper end, or the mounting table 31 may be provided on the horizontal member by spanning a horizontal member between the opposing peripheral walls 212, or the mounting member 31 may be provided on the horizontal member from the peripheral wall 212 in a cantilever shape. The horizontal member may be made to protrude and the mounting table 31 may be provided on the horizontal member.

(1.4) Heater The heater 4 heats the test specimen X1 to a set temperature. The heater 4 is feedback-controlled by the control device 7 based on the detection result of the temperature sensor 6. Feedback control is not particularly limited and includes PID (Proportional-Integral-Differential) control, PD control (differential control), P control (proportional control), etc., but it is possible to finely control the output of the heater 4. PID control is preferable from the viewpoint that it is possible.

The "set temperature" here means the target temperature of the test body X1 when heating the test body X1. The set temperature is set lower than the melting point. In this embodiment, the set temperature is set lower than the melting point and higher than the softening point. In this embodiment, the set temperature is, for example, 535°C.

Each heater 4 is a rod-shaped infrared heater that irradiates infrared rays to the test specimen X1. A plurality of heaters 4 (eight in this case) surround the mounting table 31 when viewed from above (hereinafter referred to as plan view). The plurality of infrared heaters are arranged along the inside of the peripheral wall 212 of the inner heat insulating material 21.

However, in the present invention, the number of infrared heaters is not limited to eight, and may be seven or less, or nine or more. Furthermore, the infrared heaters do not have to be arranged so as to surround the mounting table 31 in a plan view, and may be arranged either or both in the upper and lower directions with respect to the mounting table 31. In this case, the test specimen X1 may be heated by one infrared heater. A power source is connected to each infrared heater, and power is supplied to each infrared heater.

Examples of the infrared heater include a sheathed heater, a ceramic heater, a quartz heater, a carbon lamp heater, a halogen lamp heater (tungsten heater), and a carbon lamp heater is preferable from the viewpoint of thermal efficiency.

A halogen lamp heater is a heater in which a tungsten wire is passed as a heating element in a quartz tube filled with halogen gas. A halogen lamp heater emits infrared rays evenly over the entire circumference of a quartz tube. Therefore, according to the halogen lamp heater, the test specimen Infrared rays can be emitted from both the

A carbon lamp heater is a heater in which carbon fiber, which is a conductive material, is used as a heating element. Carbon lamp heaters emit more radiant energy in the mid-infrared region than halogen lamp heaters. The heating element of the carbon lamp heater is formed into a substantially planar shape, and emits infrared rays mainly in a direction perpendicular to the heating element. The heating element of a carbon lamp heater hardly emits infrared rays in a range exceeding 30 degrees with respect to a direction perpendicular to the heating element. Therefore, the carbon lamp heater has higher directivity than the halogen lamp heater, which emits radiation over 360 degrees, and can directly irradiate infrared rays onto the test specimen X1.

The infrared heater is arranged in such a direction and position that the test specimen X1 is irradiated with infrared rays. Among the infrared rays emitted from the heating element, the infrared rays that are not directly irradiated to the test specimen X1 are radiated to the inner surface of the furnace 2 and heat the furnace 2. Then, the heated furnace 2 heats the test specimen X1 by radiant heat.

The heat generation temperature (temperature of the heating element) of each infrared heater is preferably 1050°C or more and 1650°C or less, more preferably 1250°C or more and 1650°C or less, and even more preferably 1650°C. By using an infrared heater as the heater 4, it is possible to shorten the time required for the test specimen X1 to heat up from room temperature to the set temperature.

However, in the present invention, the heat generation temperature of each heater 4 may be outside the range of 1050°C or more and 1650°C or less. Further, it is preferable that the infrared heater mainly emits mid-infrared rays (the highest proportion in terms of intensity ratio), but it may also radiate mainly near-infrared rays or far infrared rays (wavelength of 25 μm or more and less than 1 mm).

(1.5) Cooling device The cooling device 5 is a device that sends gas to the test specimen X1. When the cooling device 5 sends gas to the test object X1, an air current is generated around the test object X1, and the gas around the test object X1 moves. Then, the temperature of the test body X1 decreases due to heat exchange between the test body X1 and the gas in contact with the test body X1. Therefore, "sending gas" here includes sending the gas so that it flows around the test object X1, and blowing the gas against the test object X1.

In this embodiment, gas is sent from the air supply hole 24 of the bottom wall 211, and the gas is blown onto the test specimen X1 through the through hole of the mounting table 31. When the gas is blown onto the test object X1, the gas around the test object X1 also moves at the same time. Therefore, the surface temperature of the test piece X1 can be made close to uniform, and temperature unevenness on the surface of the test piece X1 can be suppressed.

As shown in FIG. 1, the cooling device 5 includes a gas supply source 51, a flow path 52, and a control valve 53.

The supply source 51 is a base portion that supplies gas. Although the supply source 51 is a compressor in this embodiment, it may also be, for example, a blower, a cylinder containing positive pressure gas, or the like. The supply source 51 supplies compressed air (air) as a gas. However, the gas supplied from the supply source 51 is not limited to air, and may be other inert gas such as hydrogen gas or sulfur hexafluoride gas.

The flow path 52 is a path connecting the supply source 51 and the inside of the furnace 2 . Gas supplied from the supply source 51 is supplied into the furnace 2 through the flow path 52 .

The control valve 53 is provided in the flow path 52 and controls the flow rate of gas passing through the flow path 52 . Examples of the control valve 53 include a solenoid valve, an electric valve, an air-driven valve, and the like, and in this embodiment, a solenoid valve is used. The control valve 53 switches the valve body between a position that allows gas to pass through the flow path 52 (this is referred to as "ON") and a position that does not allow gas to pass through the flow path 52 (this is referred to as "OFF"). . The control valve 53 is driven and controlled by the control device 7.

(1.6) Temperature Sensor The temperature sensor 6 detects the temperature of the test specimen X1. The temperature sensor 6 can detect temperatures at a plurality of different locations on the test specimen X1. The detection result obtained by the temperature sensor 6 may be the temperature at a specific location among the multiple locations, or may be the highest or lowest temperature among the multiple locations. , a temperature obtained by averaging the temperatures at multiple locations may be used.

The temperature sensor 6 is a contact type sensor in this embodiment. However, the temperature sensor 6 is not limited to a contact type sensor, and may be a non-contact sensor. The temperature sensor 6 is disposed within the furnace 2 and outputs an electric signal generated by detecting the temperature to the control device 7.

(1.7) Control Device The control device 7 is composed of, for example, a computer having a processor and a memory. A processor performs various processes by executing programs stored in memory. As shown in FIG. 2, the control device 7 includes a determination section 71, a cooling device control section 72 that controls the cooling device 5, and a heater control section 73 that controls the output of the heater 4.

(1.7.1) Determination Unit When the electric signal from the temperature sensor 6 is input, the determination unit 71 determines whether the temperature of the test specimen X1 is equal to or higher than a threshold value. The threshold value is a numerical value for causing the cooling device control unit 72 to turn on the control valve 53 and/or for the heater control unit 73 to start reducing the output of the heater 4. That is, when the temperature of the specimen X1 becomes equal to or higher than the threshold value, air is sent to the specimen X1 by the cooling device 5, and the output of the heater 4 is suppressed, thereby suppressing a rise in the temperature of the specimen X1.

Information obtained by the judgment section 71 (hereinafter referred to as judgment information) is output to the cooling device control section 72 and the heater control section 73.

(1.7.2) Cooling device control unit The cooling device control unit 72 controls the cooling device 5. Specifically, the cooling device control unit 72 switches the control valve 53 between ON and OFF, thereby switching between a state in which gas is sent into the furnace 2 and a state in which the gas is stopped. The cooling device control unit 72 executes drive control of the control valve 53 based on the judgment information input from the judgment unit 71.

When information indicating that the temperature of the test specimen X1 is equal to or higher than the threshold is input as the determination information, the cooling device control unit 72 switches the control valve 53 to ON. When the control valve 53 is turned ON, gas is sent to the test piece X1 in the furnace 2, and as a result, the temperature of the test piece X1 decreases.

Here, the steeper the temperature gradient of heating by the heater 4 until reaching the set temperature, the more likely overshoot will occur when the set temperature is reached, but in this embodiment, the predetermined temperature (for example, The threshold value is set low (20°C or higher and 30° or lower). For this reason, since gas is sent from the cooling device 5 when the temperature of the test specimen Shoots are less likely to occur. Therefore, according to the blister tester 1 according to the present embodiment, for example, the heater 4 is outputted at the maximum output from room temperature to the set temperature, and while the test specimen X1 is heated in a short time, the set temperature is reached. When this happens, overshoot can be prevented.

The threshold value is determined appropriately by taking into consideration, for example, the size and material of the test specimen X1, the flow rate of gas supplied by the cooling device 5, the temperature of the gas, the output value of the heater 4, etc., so that overshoot can be suppressed appropriately. Set. In the blister tester 1 according to the present embodiment, the threshold value is set to 509° C. under the condition that room temperature air is supplied into the furnace 2 at a flow rate of 100 L/min for the test specimen X1 of 300 g.

The threshold value may be set to a value higher than the set temperature as long as overshoot when the temperature of the test specimen X1 reaches the set temperature can be suppressed within a predetermined range. For example, the threshold value may be set to a temperature higher than the set temperature by increasing the flow rate of the gas blown onto the test specimen X1 or by lowering the temperature of the gas below normal temperature. The term "predetermined range" as used herein means a range in which the blister test is unlikely to be affected by overshoot, and includes, for example, a range of set temperature +10°C or less. Note that an appropriate threshold value can be obtained by repeatedly testing the test specimen X1.

(1.7.3) Heater Control Unit The heater control unit 73 controls the output of the heater 4. As described above, the heater control unit 73 maintains the temperature of the test specimen X1 at the set temperature by performing feedback control on the heater 4, but in this embodiment, in the process from the initial temperature to the set temperature, the determination unit 71 However, if it is determined that the temperature of the test specimen X1 is equal to or higher than the threshold value, the output of the heater 4 is lowered.

Therefore, in addition to switching ON the control valve 53 of the cooling device 5, control is also executed to reduce the output of the heater 4. Therefore, in the process of heating the test specimen X1 from the initial temperature to the set temperature, the heater 4 It is possible to effectively suppress the occurrence of overshoot while heating in a short time by making the output as strong as possible.

After heating the test specimen X1 from the initial temperature to the set temperature, the heater control unit 73, in cooperation with the cooling device 5, performs feedback control (here, PID control) to set the set temperature to the target temperature. Execute.

The cooling device control unit 72 according to the present embodiment supplies gas to the test specimen X1 not intermittently but for a predetermined period of time (here, the test ends when the test specimen X1 reaches a temperature equal to or higher than a threshold value). The cooling device 5 is controlled so that the water is continuously fed (until the temperature is reached). In response to this, the heater control unit 73 performs feedback control on the heater 4 based on the detection result of the temperature sensor 6 during a predetermined time period.

Generally, if the output of the heater 4 is turned off for a predetermined period of time (for example, 10 seconds or more), feedback control (PID control) tends to become unstable. However, according to the blister tester 1 according to the present embodiment, the output of the heater 4 is maintained at a low output while the cooling device 5 is driven, so that it is possible to prevent feedback control from becoming unstable.

(2) Operation example Next, an operation example of the blister testing machine 1 according to the present embodiment will be described with reference to the flowchart in FIG. 3.

As shown in FIG. 3, when the blister tester 1 starts operating, the control device 7 starts the heater 4 and causes it to emit infrared rays. Thereby, the test specimen X1 is heated (steps 1 and 2).

When the specimen X1 is heated, the temperature sensor 6 detects the temperature of the specimen X1. The determining unit 71 determines whether the temperature value of the test specimen X1 is equal to or higher than the threshold value from the detection result by the temperature sensor 6 (step 3), and when determining that the temperature value of the test specimen X1 is less than the threshold value, The heater control unit 73 continues the radiation of infrared rays by the heater 4 (Step 3→Step 2).

On the other hand, when the determination unit 71 determines that the temperature value of the test specimen X1 is equal to or higher than the threshold value, the cooling device control unit 72 turns on the control valve 53 and sends gas to the test specimen X1 (step 3 → Step 4). Furthermore, the heater control unit 73 controls the output of the heater 4 to lower the output of the heater 4 than before reaching the threshold value (step 5). Thereafter, feedback control is performed on the heater 4 to maintain the temperature of the test specimen X1 at the set temperature (here, 535° C.) (step 6). For example, after the temperature of the test specimen X1 reaches the set temperature, the cooling device 5 and the heater 4 are continued to be driven for about 3 minutes.

This may cause blisters to occur on the test specimen X1. In this way, until the threshold value is reached, the heater 4 is at its maximum output, so the test specimen is heated for a total of about 3 minutes, for example, heating for about 1.8 minutes and then maintaining the temperature for 1 minute. X1 blisters may occur. Therefore, according to the blister testing machine according to this embodiment, testing can be performed in a relatively short time.

(3) Test A blister test method was carried out using the same blister tester 1 as in the above embodiment. A graph of temperature changes at this time is shown in FIG.

The set temperature in the example was 535°C, and the threshold was 509°C. The gas blown in by the cooling device 5 was room temperature air at a flow rate of 100 L/min. An infrared heater was used as the heater 4, and when the temperature of the test specimen X1 exceeded a threshold value, the output of the heater 4 was lowered.

An example in which gas was not blown into the cooling device 5 under the same conditions as in the example was used as a comparative example. Here, when the temperature of the test specimen X1 reached 509° C. or higher, the output of the heater 4 was lowered as in the example.

As shown in FIG. 4, the maximum temperature of the comparative example was 561.9°C, and an overshoot of 25°C or more was observed with respect to the set temperature of 535°C. On the other hand, the maximum temperature in the example was suppressed to 538.6°C, which was an overshoot of about 3.6°C with respect to the set temperature of 535°C.

From this test result, it was found that the cooling device 5 can appropriately suppress overshoot.

(4) Modifications The above embodiment is just one of various embodiments of the present invention. The embodiments can be modified in various ways depending on the design, etc., as long as the object of the present invention can be achieved. Modifications of the embodiment will be listed below. The modified examples described below can be applied in combination as appropriate.

In the above embodiment, the control device 7 includes the cooling device control section 72 and the heater control section 73, and performs mutually linked control, but in the present invention, the cooling device control section 72 and the heater control section 73 may be controlled independently. For example, FIGS. 5A and 5B show flowcharts for independently controlling the heater 4 and the cooling device 5.

As shown in FIG. 5(A), when the blister tester 1 starts operating, the heater control unit 73 starts the heater 4 and causes it to emit infrared rays. Thereby, the test specimen X1 is heated (steps 1A and 2A). When the specimen X1 is heated, the temperature sensor 6 detects the temperature of the specimen X1. The determining unit 71 determines whether the temperature value of the test specimen X1 is equal to or higher than the threshold value from the detection result by the temperature sensor 6 (step 3A), and if it is determined that the temperature value of the test specimen X1 is equal to or higher than the threshold value, The cooling device control unit 72 turns on the control valve 53, sends gas to the test specimen X1 (step 4A), and after a certain period of time has passed, stops the cooling device 5.

On the other hand, the heater control section 73 controls the heater 4 as follows. The heater control unit 73 starts the heater 4 (step 1B) and causes it to emit infrared rays (step 2B). Thereafter, the heater control unit 73 executes feedback control on the heater 4 regardless of whether the test specimen X1 is equal to or greater than the threshold value (step 3B), and stops the heater 4 after a certain period of time has elapsed.

Therefore, according to this modification, unlike the first embodiment, as a result, the control to reduce the output of the heater may be executed earlier than the ON switching of the control valve.

In the above embodiment, the control device 7 controlled the cooling device 5 to continuously send gas to the test specimen X1 without performing intermittent operation. Alternatively, the cooling device 5 may be controlled to send gas intermittently. For example, if the set temperature +5°C is the threshold value, and the temperature of the test specimen X1 reaches the set temperature +5°C, the control valve 53 is turned on, and then the temperature of the test specimen Control may be repeatedly executed to turn off the control valve 53 when the temperature reaches the temperature.

In the above embodiment, each heater 4 is formed into a rod shape, but in the present invention, it may be a planar heater. Further, the heater 4 is not limited to an infrared heater, and may be another heater.

In the above embodiment, the plurality of heaters 4 are arranged along the inner surface of the furnace 2, but in the present invention, the heaters 4 may be installed embedded in the wall of the furnace 2.

In the above embodiment, one control device 7 includes a cooling device control section 72 and a heater control section 73, but these do not need to be built into one housing, but may be housed in separate housings. They may be distributed and arranged.

(5) Aspect As explained above, the blister tester 1 according to the first aspect includes a test specimen holder 3 that holds the test specimen X1 and a melting point of the specimen X1 that is set to be lower than the melting point of the specimen X1. A heater 4 that heats to a set temperature, a temperature sensor 6 that detects the temperature of the test object X1, a cooling device 5 that sends gas to the test object X1, and a control device 7 that controls the cooling device 5. . When the detection result obtained from the temperature sensor 6 rises in response to heating by the heater 4 and becomes equal to or higher than a preset threshold, the control device 7 controls the cooling device 5 to send gas to the test specimen X1. control.

According to this aspect, the test specimen X1 can be quickly heated to the set temperature by the heater 4 in order to shorten the measurement time, and the overshoot that occurs accompanying this can be suppressed.

In the blister tester 1 according to the second aspect, the threshold value is set lower than the set temperature in the first aspect.

According to this aspect, overshoot that occurs when heating the test specimen X1 to the set temperature can be suppressed more effectively.

In the blister tester 1 according to the third aspect, in the first or second aspect, the heater 4 is an infrared heater that irradiates infrared rays to the test specimen X1.

According to this aspect, the heating time when heating from the initial temperature to the set temperature can be shortened, and overshoot that tends to occur at that time can be suppressed.

The blister testing machine 1 according to the fourth aspect, in any one of the first to third aspects, further includes a heater control section 73 that controls the output of the heater 4. The heater control unit 73 controls the heater 4 to lower the output of the heater 4 when the detection result obtained from the temperature sensor 6 increases in response to heating by the heater 4 and becomes equal to or higher than a threshold value.

According to this aspect, overshoot that occurs when heating the test specimen X1 to the set temperature can be suppressed more effectively.

In the blister tester 1 according to the fifth aspect, in the fourth aspect, the control device 7 controls the cooling device 5 to maintain a state of sending gas to the test specimen X1 for a predetermined period of time. The heater control unit 73 controls the output of the heater 4 based on the detection result of the temperature sensor 6 during a predetermined period of time.

According to this aspect, stable feedback control for controlling the heater 4 can be achieved.

In the blister tester 1 according to the sixth aspect, in any one of the first to fifth aspects, the gas is air.

According to this aspect, gas can be obtained from the environment in which the blister tester 1 is installed, without separately preparing the gas.

In the blister tester 1 according to the seventh aspect, in any one of the first to sixth aspects, the cooling device 5 is configured to blow gas against the test specimen X1.

According to this aspect, the temperature of the test specimen X1 can be effectively lowered, and overshoot that occurs when the test specimen X1 is heated to the set temperature can be suppressed more effectively.

The testing machine according to the eighth aspect further includes a furnace 2 that accommodates a test specimen holder 3. The cooling device 5 includes a gas supply source 51 , a flow path 52 connecting the supply source 51 and the inside of the furnace 2 , and a control valve 53 provided in the flow path 52 and driven and controlled by the control device 7 .

According to this aspect, the cooling device 5 with a simplified configuration can be installed.

The blister test method according to the ninth aspect is a blister test method in which the test sample X1 is heated to a set temperature that is set below the melting point of the test sample X1, and blisters appearing on the test sample X1 are evaluated. When the temperature of the test body X1 increases as a result of heating the test body X1 and the temperature of the test body X1 reaches a predetermined temperature value or higher, cooling gas is sent to the test body X1.

According to this aspect, overshoot that occurs when heating the test specimen X1 to the set temperature can be suppressed.

The configurations according to the second to eighth aspects are not essential to the blister testing machine 1 and can be omitted as appropriate.

1 Blister tester 2 Furnace 3 Test specimen holder 4 Heater 5 Cooling device 51 Supply source 52 Flow path 53 Control valve 6 Temperature sensor 7 Control device X1 Test specimen

Claims (9)

a test specimen holder that holds the test specimen;
a heater that heats the test specimen to a set temperature lower than the melting point of the test specimen;
a temperature sensor that detects the temperature of the test specimen;
a cooling device that sends gas to the test specimen;
a control device that controls the cooling device;
Equipped with
The control device controls the cooling to send the gas to the test specimen when the detection result obtained from the temperature sensor increases in response to heating by the heater and becomes equal to or higher than a preset threshold. control the device,
Blister testing machine. The threshold value is set lower than the set temperature,
The blister testing machine according to claim 1. The heater is an infrared heater that irradiates the test specimen with infrared rays,
The blister testing machine according to claim 1 or claim 2. further comprising a heater control unit that controls the output of the heater,
The heater control unit controls the heater to reduce the output of the heater when the detection result obtained from the temperature sensor increases in response to heating by the heater and becomes equal to or higher than the threshold value.
The blister tester according to any one of claims 1 to 3. The control device controls the cooling device to maintain a state in which the gas is sent to the test specimen for a predetermined period of time,
The heater control unit controls the output of the heater based on the detection result of the temperature sensor during the predetermined time period.
The blister testing machine according to claim 4. the gas is air;
The blister tester according to any one of claims 1 to 5. The blister testing machine according to any one of claims 1 to 6, wherein the cooling device is configured to blow the gas against the test specimen. further comprising a furnace accommodating the test specimen holder,
The cooling device includes:
a source of the gas;
a flow path connecting the supply source and the inside of the furnace;
a control valve provided in the flow path and driven and controlled by the control device;
has,
The blister tester according to any one of claims 1 to 7. A blister test method that evaluates blisters appearing on the test specimen by heating the test specimen to a set temperature set below the melting point of the test specimen,
A blister test method in which cooling gas is sent to the test body when the temperature of the test body rises as a result of heating the test body and the temperature of the test body exceeds a predetermined temperature value.

Images