A device for testing the melt shrinkage rate of amorphous alloys based on optical levers and its usage method

Abstract

This invention relates to an apparatus for testing the shrinkage rate of amorphous alloy melt based on an optical lever and its method of use. It addresses the problem that existing technologies cannot test the shrinkage rate of amorphous alloy melts. The testing apparatus consists of a scale, a vacuum furnace, an infrared thermometer, a K-type thermocouple, a lifting support, a laser generator, an induction coil, a crucible, a melt shrinkage testing mold, an optical lever support, an optical lever, a thin-film slider support, and a slider assembly. The method of use is as follows: 1. Place the amorphous alloy in the crucible, then evacuate and introduce argon gas; 2. Turn on the laser generator; 3. Induction melt the amorphous alloy; 4. Cast the amorphous alloy melt into the melt shrinkage testing mold, record the changes in the scale corresponding to the laser beam, record the temperature changes of the amorphous alloy melt, and thus obtain the correlation between the shrinkage rate of the amorphous alloy melt and the melt temperature.

Description

Technical Field

[0001] This invention relates to a device for testing the shrinkage rate of amorphous alloy melt and its usage method. Background Technology

[0002] Numerous casting defects exist in metal casting processes, such as shrinkage cavities, porosity, stress, and deformation. The fundamental cause is the shrinkage of the casting alloy. Shrinkage is the phenomenon of volume reduction that occurs during the cooling process of a casting in the liquid, solidification, and solid-state phases. For general alloys, the sum of solidification shrinkage (3%–5%) and liquid shrinkage is usually greater than solid-state shrinkage. Without proper feeding, defects such as shrinkage cavities and porosity are prone to occur in castings. Therefore, studying the shrinkage characteristics of alloys is a prerequisite for obtaining castings with good metallurgical quality. Amorphous alloys are usually prepared under relatively high cooling conditions, and their microstructure retains the liquid state, typically without a solidification shrinkage process. The shrinkage characteristics of amorphous alloy melts during the glass transition differ from those of crystalline alloys. Currently, there is a lack of relevant data on the shrinkage process of amorphous alloy melts, and related research is scarce. Therefore, obtaining the correspondence between cooling and shrinkage of amorphous alloy melts is crucial for forming amorphous alloy castings with precise dimensions. Summary of the Invention

[0003] The present invention aims to solve the problem that existing technologies cannot test the shrinkage rate of amorphous alloy melts, and thus provides an amorphous alloy melt shrinkage rate testing device based on an optical lever and its usage method.

[0004] A device for testing the shrinkage rate of amorphous alloy melt based on an optical lever, comprising a scale, a vacuum furnace body, an infrared thermometer, a K-type thermocouple, a lifting bracket, a laser generator, an induction coil, a crucible, a melt shrinkage test mold, an optical lever bracket, an optical lever, a thin-film slider bracket, and a slider assembly;

[0005] The vacuum furnace body is equipped with a flange for melt temperature monitoring on the top and a rotary dynamic sealing mechanism on the side wall. A transparent window is provided on the furnace door of the vacuum furnace body. An infrared thermometer is located outside the vacuum furnace body and directly above the flange for melt temperature monitoring.

[0006] The K-type thermocouple, lifting bracket, induction coil, crucible, melt shrinkage test mold, optical lever bracket, optical lever, thin-film slider bracket and slider assembly are arranged inside the vacuum furnace; the lifting bracket is arranged at the bottom of the vacuum furnace, and the melt shrinkage test mold is arranged on the lifting bracket;

[0007] The melt shrinkage test mold has a U-shaped structure consisting of a pouring cup, a vertical runner, a horizontal runner, and a vertical cavity connected in sequence. The horizontal height of the outlet cross-section of the pouring cup is higher than the upper end face of the vertical cavity. A thin-plate slider support is provided on the upper end face of the melt shrinkage test mold. The thickness of the thin-plate slider support is 0.3mm to 0.8mm. A thermocouple insertion hole is provided on the side of the vertical cavity, and one end of a K-type thermocouple passes through the thermocouple insertion hole and is placed inside the vertical cavity. A light lever support is provided on the side wall of the melt shrinkage test mold, and the upper end face of the light lever support is at the same horizontal plane as the upper end face of the melt shrinkage test mold.

[0008] The slider assembly consists of a slider, a connecting rod, and an overlapping piece. The slider is disposed on the upper part of the vertical cavity and is clearance-fitted. The upper end of the slider is connected to one end of the connecting rod, and the other end of the connecting rod passes through the thin-plate slider bracket and is connected to the overlapping piece. The overlapping piece overlaps the upper surface of the thin-plate slider bracket.

[0009] The optical lever consists of a front foot tip, a bracket, a reflector, a horizontal rod, and a horizontal rod tip. The lower end of the front foot tip is set on the upper end face of the optical lever bracket, the horizontal rod tip is in contact with the upper end face of the overlapping piece, and the reflector corresponds to the position of the transparent window on the vacuum furnace door.

[0010] An induction coil is installed on the outside of the crucible, and the end of the induction coil passes through the rotary dynamic sealing mechanism and is fixed, so that the crucible is positioned directly above the pouring cup and simultaneously directly below the flange used for monitoring the melt temperature.

[0011] The scale is located on the outside of the vacuum furnace body, and the scale of the scale corresponds to the position of the transparent window on the furnace door of the vacuum furnace body. A laser generator is set between the scale and the transparent window.

[0012] A method for using an optical lever-based device for testing the shrinkage rate of amorphous alloy melts comprises the following steps:

[0013] 1. Set the melt shrinkage test mold on the lifting bracket, place the amorphous alloy in the crucible, then close the vacuum furnace and evacuate the vacuum, and then introduce argon gas;

[0014] 2. Turn on the laser generator and position the laser beam directly onto the reflector of the optical lever;

[0015] 3. The amorphous alloy in the crucible is induction melted using an induction coil to obtain an amorphous alloy melt. The temperature of the melt is measured using an infrared thermometer to determine whether it has reached the preset temperature.

[0016] 4. By rotating the induction coil, the amorphous alloy melt in the crucible is poured into the vertical cavity of the melt shrinkage test mold. The optical lever and the K-type thermocouple both start to respond. The change of the scale corresponding to the laser emitted by the laser generator is recorded by the reflection of the laser mirror on the scale. At the same time, the temperature change of the amorphous alloy melt is recorded. The shrinkage of the amorphous alloy melt in the vertical cavity is calculated by formula (a) and converted into the shrinkage rate by formula (b). Then, the relationship between the shrinkage rate of the amorphous alloy melt and the melt temperature is obtained.

[0017]

[0018] In the formula, d is the vertical distance from the tip of the front foot of the optical lever to the tip of the horizontal rod, in mm; D is the vertical distance from the reflector to the scale in the optical lever, in mm; Δl is the shrinkage of the amorphous alloy melt in the vertical cavity along its length, in mm; ΔL is the change in scale reading when the amorphous alloy melt shrinks by Δl, in mm; ε is the shrinkage rate of the amorphous alloy melt; l C The initial length of the amorphous alloy melt in the vertical cavity is expressed in mm.

[0019] The beneficial effects of this invention are:

[0020] This invention, based on the preparation process of reduced amorphous alloys, utilizes the principle of optical lever amplification to solve the problem of the difficulty in measuring the small shrinkage rate of amorphous alloy melts. Materials such as copper, steel, and graphite can be used as mold materials to ensure that the amorphous alloy melt cools and solidifies at a sufficient cooling rate, simultaneously enabling the measurement of the amorphous alloy melt shrinkage rate. Furthermore, this invention allows for control of the melt melting temperature and furnace pressure, facilitating testing under different preparation process conditions. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the amorphous alloy melt shrinkage rate testing device based on optical lever of the present invention;

[0022] Figure 2 This is a schematic diagram showing the assembly of the induction coil, crucible, melt shrinkage test mold, optical lever support, optical lever, thin-film slider support, and slider assembly of the present invention.

[0023] Figure 3 This is a schematic diagram showing the assembly of the melt shrinkage test mold, the thin-sheet slider support, and the slider assembly of the present invention.

[0024] Figure 4 This is a schematic diagram of the optical lever structure of the present invention;

[0025] Figure 5 This is a schematic diagram of the measurement principle of the amorphous alloy melt shrinkage rate testing device based on optical lever of the present invention;

[0026] Figure 6 The cooling curve of the amorphous alloy melt tested by the K-type thermocouple in Example 1;

[0027] Figure 7 The curve showing the relationship between the shrinkage rate and temperature of the amorphous alloy melt in Example 1;

[0028] Figure 8 The image shows the X-ray diffraction pattern of the amorphous alloy melt after cooling to room temperature in Example 1. Detailed Implementation

[0029] Specific implementation method one, combined with Figures 1 to 4 Detailed description: This embodiment is a device for testing the shrinkage rate of amorphous alloy melt based on an optical lever. It consists of a scale 1, a vacuum furnace body 2, an infrared thermometer 3, a K-type thermocouple 6, a lifting bracket 7, a laser generator 9, an induction coil 10, a crucible 11, a melt shrinkage test mold 12, an optical lever bracket 13, an optical lever 14, a thin-film slider bracket 15, and a slider assembly 16.

[0030] The vacuum furnace body 2 is equipped with a flange for monitoring melt temperature on the top and a rotary dynamic sealing mechanism on the side wall. A transparent window is provided on the furnace door of the vacuum furnace body 2. The infrared thermometer 3 is located outside the vacuum furnace body 2 and directly above the flange for monitoring melt temperature.

[0031] The K-type thermocouple 6, lifting bracket 7, induction coil 10, crucible 11, melt shrinkage test mold 12, optical lever bracket 13, optical lever 14, thin-film slider bracket 15 and slider assembly 16 are disposed inside the vacuum furnace body 2; the lifting bracket 7 is disposed at the bottom of the vacuum furnace body 2, and the melt shrinkage test mold 12 is disposed on the lifting bracket 7.

[0032] The melt shrinkage test mold 12 has a U-shaped structure consisting of a pouring cup 12-1, a vertical runner 12-2, a horizontal runner 12-3, and a vertical cavity 12-4 connected in sequence. The horizontal height of the outlet cross-section of the pouring cup 12-1 is higher than the upper surface of the vertical cavity 12-4. A thin-plate slider support 15 is provided on the upper surface of the melt shrinkage test mold 12. The thickness of the thin-plate slider support 15 is 0.3mm to 0.8mm. A thermocouple insertion hole is provided on the side of the vertical cavity 12-4. One end of a K-type thermocouple 6 passes through the thermocouple insertion hole and is placed inside the vertical cavity 12-4. A light lever support 13 is provided on the side wall of the melt shrinkage test mold 12, and the upper surface of the light lever support 13 is on the same horizontal plane as the upper surface of the melt shrinkage test mold 12.

[0033] The slider assembly 16 consists of a slider 16-1, a connecting rod 16-2, and an overlapping piece 16-3. The slider 16-1 is disposed on the upper part of the vertical cavity 12-4 and is clearance-fitted. The upper end of the slider 16-1 is connected to one end of the connecting rod 16-2. The other end of the connecting rod 16-2 passes through the thin-plate slider bracket 15 and is connected to the overlapping piece 16-3. The overlapping piece 16-3 overlaps the upper surface of the thin-plate slider bracket 15.

[0034] The optical lever 14 is composed of a front foot tip 17, a bracket 18, a reflector 19, a horizontal rod 20, and a horizontal rod foot tip 21. The lower end of the front foot tip 17 is set on the upper end face of the optical lever bracket 13, the horizontal rod foot tip 21 is in contact with the upper end face of the overlapping piece 16-3, and the reflector 19 corresponds to the position of the transparent window on the furnace door of the vacuum furnace body 2.

[0035] An induction coil 10 is provided on the outside of the crucible 11. The end of the induction coil 10 passes through the rotary dynamic sealing mechanism and is fixed, so that the crucible 11 is positioned directly above the pouring cup 12-1 and simultaneously directly below the flange used for monitoring the melt temperature.

[0036] The scale 1 is located outside the vacuum furnace body 2, and the scale of the scale 1 corresponds to the position of the transparent window on the furnace door of the vacuum furnace body 2. A laser generator 9 is set between the scale 1 and the transparent window.

[0037] In this specific embodiment, the infrared thermometer 3 is installed outside the vacuum furnace body 2, directly above the crucible 11, and can monitor the temperature of the alloy melt in real time through the observation window of the flange on the vacuum furnace body 2 used for melt temperature monitoring.

[0038] In this specific embodiment, the melt shrinkage test mold 12 adopts a bottom-cast design to reduce the impact of runner shrinkage on the measurement data. The mold is equipped with a slider assembly 16, which can slide up and down according to the changes in melt volume.

[0039] In this specific embodiment, the melt shrinkage test mold 12 is placed on the lifting bracket 7, and the height of the mold in the furnace can be adjusted by the lifting bracket 7.

[0040] In this specific embodiment, the optical lever 14 is placed on the optical lever support 13 of the melt shrinkage test mold 12, and the tip 21 of the horizontal rod of the optical lever 14 contacts the overlapping piece 16-3 of the slider assembly 16. The optical lever 14 can deflect at an angle as the position of the slider assembly 16 changes.

[0041] In this specific embodiment, the scale 1 is located outside the vacuum furnace body 2, facing the transparent window of the furnace door of the vacuum furnace body 2. A laser generator 9 is set between the scale 1 and the observation window. The laser emitted by the laser generator 9 can be projected through the transparent window onto the reflector 19 of the optical lever 14 and reflected back onto the scale 1. When the optical lever 14 deflects at an angle, the reflector 19 also deflects accordingly, and the position of the laser reflected onto the scale 1 also changes.

[0042] The vertical cavity 12-4 of the melt shrinkage test mold 12 is provided with a thermocouple insertion hole. One end of the K-type thermocouple 6 passes through the thermocouple insertion hole and is placed inside the vertical cavity 12-4 to measure the temperature change of the amorphous alloy melt during the cooling process.

[0043] The beneficial effects of this specific implementation method are:

[0044] This specific embodiment, based on the preparation process of reduced amorphous alloys, utilizes the principle of optical lever amplification to solve the problem of the small shrinkage rate of amorphous alloy melts, which is difficult to test. Materials such as copper, steel, and graphite can be used as mold materials to ensure that the amorphous alloy melt cools and solidifies at a sufficient cooling rate to form the amorphous alloy, while simultaneously enabling the measurement of the amorphous alloy melt shrinkage rate. Furthermore, this specific embodiment allows for control of the melt melting temperature and furnace pressure, facilitating testing under different preparation process conditions.

[0045] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that a camera 8 is installed outside the vacuum furnace body 2, and the position of the camera 8 corresponds to the scale of the ruler 1. Everything else is the same as in Specific Implementation Method One.

[0046] In this specific embodiment, a camera 8 is used to record in real time the scale readings reflected by the laser onto the ruler 1.

[0047] Specific Implementation Method Three: This implementation method differs from Specific Implementation Method One or Two in that: a flange for thermocouple wiring is provided on the side wall of the vacuum furnace body 2; the other end of the K-type thermocouple 6 is electrically connected to the temperature data acquisition device 5 through the flange for thermocouple wiring, and the temperature data acquisition device 5 is connected to the computer 4 through an RJ45 interface. Everything else is the same as in Specific Implementation Method One or Two.

[0048] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that the vacuum furnace body 2 is connected to the secondary vacuum system. Otherwise, it is the same as Specific Implementation Methods One to Three.

[0049] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that the pouring cup 12-1 has a conical structure, and the inlet cross-section of the pouring cup 12-1 is larger than the outlet cross-section of the pouring cup 12-1. Everything else is the same as in Specific Implementation Methods One to Four.

[0050] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that: the vertical runner 12-2, the horizontal runner 12-3, and the vertical cavity 12-4 are all cylindrical cavity structures; let the diameter of the vertical runner 12-2 and the horizontal runner 12-3 be d. C The diameter of the vertical cavity 12-4 is D. C D C ≥d C Everything else is the same as in specific implementation methods one through five.

[0051] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in that the reflector 19 is mounted on the support 18, the bottom of the support 18 has a front tip 17, a horizontal rod 20 is mounted on one side end face of the support 18, and a horizontal rod tip 21 is mounted at the end of the horizontal rod 20. Everything else is the same as in Specific Implementation Methods One to Six.

[0052] Specific implementation method eight, combined with Figure 5 Detailed explanation: This embodiment describes a method for using an amorphous alloy melt shrinkage rate testing device based on an optical lever, which is carried out according to the following steps:

[0053] 1. Place the melt shrinkage test mold 12 on the lifting bracket 7, place the amorphous alloy in the crucible 11, then close the vacuum furnace body 2 and evacuate the vacuum, and then introduce argon gas.

[0054] 2. Turn on the laser generator 9 and position the laser beam directly onto the reflector 19 of the optical lever 14;

[0055] 3. The amorphous alloy in the crucible 11 is induction melted using the induction coil 10 to obtain the amorphous alloy melt. The temperature of the melt is measured using the infrared thermometer 3 to determine whether it has reached the preset temperature.

[0056] Fourth, by rotating the induction coil 10, the amorphous alloy melt in the crucible 11 is poured into the vertical cavity 12-4 of the melt shrinkage test mold 12. The optical lever 14 and the K-type thermocouple 6 both start to respond. The change of the scale corresponding to the laser emitted by the laser generator 9 is recorded by the reflection of the reflector 19 on the scale 1. At the same time, the temperature change of the amorphous alloy melt is recorded. The shrinkage of the amorphous alloy melt in the vertical cavity 12-4 in the length direction is calculated by formula (a) and converted into the shrinkage rate by formula (b). Then, the corresponding relationship between the shrinkage rate of the amorphous alloy melt and the melt temperature is obtained.

[0057]

[0058] In the formula, d is the vertical distance from the front tip 17 of the optical lever 14 to the tip 21 of the horizontal rod, in mm; D is the vertical distance from the reflector 19 of the optical lever 14 to the scale 1, in mm; Δl is the amount of shrinkage of the amorphous alloy melt in the vertical cavity 12-4 along its length, in mm; ΔL is the change in the reading of the scale 1 when the amorphous alloy melt shrinks by Δl, in mm; ε is the shrinkage rate of the amorphous alloy melt; l C The initial length of the amorphous alloy melt in the vertical cavity 12-4 is in the longitudinal direction, in mm.

[0059] Because the horizontal height of the outlet cross-section of the pouring cup 12-1 of the melt shrinkage test mold 12 is higher than the upper surface of the vertical cavity 12-4, according to the principle of communicating vessels, when the amorphous alloy melt fills the vertical cavity 12-4 and contacts the lower surface of the slider 16-1, the upper surface of the overlapping piece 16-3 of the slider assembly 16 rises from its original position 1 to position 2. Then, as the temperature of the amorphous alloy melt decreases and it shrinks, the upper surface of the overlapping piece 16-3 of the slider assembly 16 falls from position 2 to position 3. Correspondingly, the laser also has a corresponding position on the scale, such as... Figure 5 As shown.

[0060] In this specific embodiment, the amorphous alloy melting and casting solidification are both carried out under vacuum and argon protection conditions.

[0061] In this specific embodiment, a camera 8 records the changes in the scale corresponding to the reflection of the laser emitted by the laser generator 9 on a ruler. Simultaneously, a temperature data acquisition device 5 and a computer 4 record the temperature changes of the amorphous alloy melt. Using the response time of each sensor as a starting point, the relationship between the shrinkage rate of the amorphous alloy melt and the melt temperature can be obtained.

[0062] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Method Eight in that: in step four, when the amorphous alloy melt fills the vertical cavity 12-4 and contacts the lower end face of the slider 16-1, the upper end face of the overlapping piece 16-3 rises from its original position 1 to position 2. As the temperature of the amorphous alloy melt decreases, it contracts, and the upper end face of the overlapping piece 16-3 lowers to position 3. Everything else is the same as in Specific Implementation Method Eight.

[0063] Specific Implementation Method Ten: This implementation method differs from Specific Implementation Method Eight or Nine in that: Formula (a) in step four is specifically derived from formulas (c) to (l), and formula (b) is specifically calculated from formulas (a) and (m), as follows:

[0064]

[0065] When θ→0:

[0066]

[0067] Then we have:

[0068]

[0069] Similarly, we have:

[0070]

[0071] When γ→0

[0072]

[0073] Then we have:

[0074]

[0075] Therefore:

[0076]

[0077] The shrinkage rate of amorphous alloy melt can be calculated by the following formula:

[0078] l C =l y +Δl0(m)

[0079]

[0080] In the formula, d is the vertical distance from the front foot 17 of the optical lever 14 to the horizontal rod foot 21, in mm; D is the vertical distance from the reflector 19 of the optical lever 14 to the scale 1, in mm; ε is the shrinkage rate of the amorphous alloy melt; l C The initial length of the amorphous alloy melt in the vertical cavity 12-4 along its longitudinal direction, in mm; yθ is the initial distance from the lower end face of slider 16-1 to the bottom of vertical cavity 12-4 before the amorphous alloy melt enters the vertical cavity 12-4; θ is the angle between the horizontal rod 20 and the horizontal direction when the upper end face of the overlapping piece 16-3 rises from its original position 1 to position 2; Δl0 is the distance from the upper end face of the overlapping piece 16-3 rising from its original position 1 to position 2, in mm; ΔL0 is the change in the reading of the corresponding scale 1 when the upper end face of the overlapping piece 16-3 rises from its original position 1 to position 2, in mm. γ is the angle between the horizontal rod 20 and the horizontal direction when the upper end face of the overlapping piece 16-3 descends from position 2 to position 3; Δl is the amount of contraction of the amorphous alloy melt in the vertical cavity 12-4 along its length, i.e., the distance from the upper end face of the overlapping piece 16-3 to position 3, in mm; ΔL is the change in the reading of the scale 1 corresponding to the contraction Δl of the amorphous alloy melt, i.e., the change in the reading of the scale 1 corresponding to the descending of the upper end face of the overlapping piece 16-3 from position 2 to position 3, in mm. Other aspects are the same as in specific embodiments eight or nine.

[0081] The beneficial effects of the present invention are verified using the following embodiments:

[0082] Example 1:

[0083] A device for testing the shrinkage rate of amorphous alloy melt based on an optical lever, comprising a scale 1, a vacuum furnace body 2, an infrared thermometer 3, a K-type thermocouple 6, a lifting bracket 7, a laser generator 9, an induction coil 10, a crucible 11, a melt shrinkage test mold 12, an optical lever bracket 13, an optical lever 14, a thin-film slider bracket 15, and a slider assembly 16.

[0084] The vacuum furnace body 2 is equipped with a flange for monitoring melt temperature on the top and a rotary dynamic sealing mechanism on the side wall. A transparent window is provided on the furnace door of the vacuum furnace body 2. The infrared thermometer 3 is located outside the vacuum furnace body 2 and directly above the flange for monitoring melt temperature.

[0085] The K-type thermocouple 6, lifting bracket 7, induction coil 10, crucible 11, melt shrinkage test mold 12, optical lever bracket 13, optical lever 14, thin-film slider bracket 15 and slider assembly 16 are disposed inside the vacuum furnace body 2; the lifting bracket 7 is disposed at the bottom of the vacuum furnace body 2, and the melt shrinkage test mold 12 is disposed on the lifting bracket 7.

[0086] The melt shrinkage test mold 12 has a U-shaped structure consisting of a pouring cup 12-1, a vertical runner 12-2, a horizontal runner 12-3, and a vertical cavity 12-4 connected in sequence. The horizontal height of the outlet cross-section of the pouring cup 12-1 is higher than the upper surface of the vertical cavity 12-4. A thin-plate slider support 15 is provided on the upper surface of the melt shrinkage test mold 12. The thickness of the thin-plate slider support 15 is 0.5 mm. A thermocouple insertion hole is provided on the side of the vertical cavity 12-4. One end of a K-type thermocouple 6 passes through the thermocouple insertion hole and is placed inside the vertical cavity 12-4. A light lever support 13 is provided on the side wall of the melt shrinkage test mold 12, and the upper surface of the light lever support 13 is on the same horizontal plane as the upper surface of the melt shrinkage test mold 12.

[0087] The slider assembly 16 consists of a slider 16-1, a connecting rod 16-2, and an overlapping piece 16-3. The slider 16-1 is disposed on the upper part of the vertical cavity 12-4 and is clearance-fitted. The upper end of the slider 16-1 is connected to one end of the connecting rod 16-2. The other end of the connecting rod 16-2 passes through the thin-plate slider bracket 15 and is connected to the overlapping piece 16-3. The overlapping piece 16-3 overlaps the upper surface of the thin-plate slider bracket 15.

[0088] The optical lever 14 is composed of a front foot tip 17, a bracket 18, a reflector 19, a horizontal rod 20, and a horizontal rod foot tip 21. The lower end of the front foot tip 17 is set on the upper end face of the optical lever bracket 13, the horizontal rod foot tip 21 is in contact with the upper end face of the overlapping piece 16-3, and the reflector 19 corresponds to the position of the transparent window on the furnace door of the vacuum furnace body 2.

[0089] An induction coil 10 is provided on the outside of the crucible 11. The end of the induction coil 10 passes through the rotary dynamic sealing mechanism and is fixed, so that the crucible 11 is positioned directly above the pouring cup 12-1 and simultaneously directly below the flange used for monitoring the melt temperature.

[0090] The scale 1 is located outside the vacuum furnace body 2, and the scale of the scale 1 corresponds to the position of the transparent window on the furnace door of the vacuum furnace body 2. A laser generator 9 is set between the scale 1 and the transparent window.

[0091] A camera 8 is installed on the outside of the vacuum furnace body 2, and the position of the camera 8 corresponds to the scale of the ruler 1.

[0092] The side wall of the vacuum furnace body 2 is provided with a flange for thermocouple wiring; the other end of the K-type thermocouple 6 is electrically connected to the temperature data acquisition device 5 through the flange for thermocouple wiring, and the temperature data acquisition device 5 is connected to the computer 4 through an RJ45 interface.

[0093] The vacuum furnace body 2 is connected to the secondary vacuum system.

[0094] The pouring cup 12-1 has a conical structure, and the inlet cross-section of the pouring cup 12-1 is larger than the outlet cross-section of the pouring cup 12-1.

[0095] The vertical runner 12-2, the horizontal runner 12-3, and the vertical cavity 12-4 are all cylindrical cavity structures; let the diameter of the vertical runner 12-2 and the horizontal runner 12-3 be d. C The diameter of the vertical cavity 12-4 is D. C d C =9mm, D C =10mm.

[0096] The reflector 19 is mounted on the bracket 18. The bottom of the bracket 18 is provided with a front foot 17, and a horizontal bar 20 is provided on one side end face of the bracket 18. The end of the horizontal bar 20 is provided with a horizontal bar foot 21.

[0097] The melt shrinkage test mold 12, the thin-film slider bracket 15, and the slider assembly 16 are all made of copper.

[0098] The above-mentioned method for using the amorphous alloy melt shrinkage rate testing device based on optical lever is carried out according to the following steps:

[0099] 1. Place the melt shrinkage test mold 12 on the lifting support 7, place the amorphous alloy in the crucible 11, then close the vacuum furnace 2. First, use a mechanical pump to evacuate to 10 Pa, then use a molecular pump to evacuate to 10 Pa. -3 Pa, then argon gas is introduced to 50 kPa;

[0100] The amorphous alloy mentioned is Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 (Brand name: Vit1);

[0101] 2. Turn on the laser generator 9 and position the laser directly on the reflector 19 of the optical lever 14. Turn on the camera 8 to focus and adjust the position of the scale 1 so that the camera 8 is directly facing the position of the laser reflected by the reflector 19 of the optical lever 14 onto the scale 1, in order to record the change in scale value. Turn on the temperature data acquisition device 5 and the computer 4 to record the temperature of the amorphous alloy melt entering the vertical cavity 12-4.

[0102] 3. The amorphous alloy in the crucible 11 is induction melted using the induction coil 10 to obtain the amorphous alloy melt. The temperature of the melt is measured using the infrared thermometer 3 to determine whether it has reached the preset temperature.

[0103] 4. By rotating the induction coil 10, the amorphous alloy melt in the crucible 11 is poured into the vertical cavity 12-4 of the melt shrinkage test mold 12. The optical lever 14 and the K-type thermocouple 6 both start to respond. The change of the scale corresponding to the laser emitted by the laser generator 9 is recorded by the reflection of the reflector 19 on the scale 1. At the same time, the temperature change of the amorphous alloy melt is recorded. After the amorphous alloy melt cools to room temperature, the shrinkage of the amorphous alloy melt in the length direction in the vertical cavity 12-4 is calculated by formula (a) and converted into the shrinkage rate by formula (b). Then, the corresponding relationship between the shrinkage rate of the amorphous alloy melt and the melt temperature is obtained.

[0104]

[0105] In the formula, d is the vertical distance from the front tip 17 of the optical lever 14 to the tip 21 of the horizontal rod, in mm; D is the vertical distance from the reflector 19 of the optical lever 14 to the scale 1, in mm; Δl is the amount of shrinkage of the amorphous alloy melt in the vertical cavity 12-4 along its length, in mm; ΔL is the change in the reading of the scale 1 when the amorphous alloy melt shrinks by Δl, in mm; ε is the shrinkage rate of the amorphous alloy melt; l C The initial length of the amorphous alloy melt in the vertical cavity 12-4 is in the longitudinal direction, in mm;

[0106] In step four, when the amorphous alloy melt fills the vertical cavity 12-4 and contacts the lower end face of the slider 16-1, the upper end face of the overlapping piece 16-3 rises from the original position 1 to position 2. As the temperature of the amorphous alloy melt decreases, it contracts, and the upper end face of the overlapping piece 16-3 lowers to position 3.

[0107] Formula (a) in step four is derived from formulas (c) to (l), and formula (b) is calculated from formulas (a) and (m), as follows:

[0108]

[0109] When θ→0:

[0110]

[0111] Then we have:

[0112]

[0113] Similarly, we have:

[0114]

[0115] When γ→0

[0116]

[0117] Then we have:

[0118]

[0119] Therefore:

[0120]

[0121] The shrinkage rate of amorphous alloy melt can be calculated by the following formula:

[0122] l C =l y +Δl0(m)

[0123]

[0124] In the formula, d is the vertical distance from the front foot 17 of the optical lever 14 to the horizontal rod foot 21, in mm; D is the vertical distance from the reflector 19 of the optical lever 14 to the scale 1, in mm; ε is the shrinkage rate of the amorphous alloy melt; l C The initial length of the amorphous alloy melt in the vertical cavity 12-4 along its longitudinal direction, in mm; y θ is the initial distance from the lower end face of slider 16-1 to the bottom of vertical cavity 12-4 before the amorphous alloy melt enters the vertical cavity 12-4; θ is the angle between the horizontal rod 20 and the horizontal direction when the upper end face of the overlapping piece 16-3 rises from its original position 1 to position 2; Δl0 is the distance from the upper end face of the overlapping piece 16-3 rising from its original position 1 to position 2, in mm; ΔL0 is the change in the reading of the corresponding scale 1 when the upper end face of the overlapping piece 16-3 rises from its original position 1 to position 2, in mm. γ is the angle between the horizontal rod 20 and the horizontal direction when the upper end face of the overlapping piece 16-3 descends from position 2 to position 3; Δl is the amount of shrinkage of the amorphous alloy melt in the vertical cavity 12-4 along its length, that is, the distance from the upper end face of the overlapping piece 16-3 descending from position 2 to position 3, in mm; ΔL is the change in the reading of the scale 1 corresponding to the shrinkage Δl of the amorphous alloy melt, that is, the change in the reading of the scale 1 corresponding to the descending of the upper end face of the overlapping piece 16-3 from position 2 to position 3, in mm.

[0125] This embodiment uses the response of type K thermocouple 6 and optical lever 14 as the starting point for data processing.

[0126] The optical lever 14 described in this embodiment was purchased from Changchun Lepu Technology Co., Ltd., and its model number is YMC-IV.

[0127] Figure 6The figure shows the cooling curve of the amorphous alloy melt tested by the K-type thermocouple in Example 1. As can be seen from the figure, the cooling process of the amorphous alloy melt can be divided into a rapid cooling stage, a transition stage, and a slow cooling stage. In the initial stage of cooling, the temperature of the amorphous alloy melt drops rapidly, reaching the glass transition temperature of the alloy (approximately 357°C) at 4.2 s. This indicates that the copper melt shrinkage test mold 12 can provide a high cooling rate for the alloy melt.

[0128] Figure 7 The graph shows the relationship between the shrinkage rate of the amorphous alloy melt and temperature in Example 1. As can be seen from the graph, the rate of change in the shrinkage rate of the amorphous alloy melt changes around 390°C. This temperature is slightly higher than the glass transition temperature of the amorphous alloy, 357°C. Below this temperature, the alloy shrinks faster than above it. This indicates that the microstructure of the amorphous alloy melt changes at this temperature, and that this transition has a transitional phase, suggesting that the glass transition of the amorphous alloy melt is completed within a specific temperature range.

[0129] Figure 8 This is an X-ray diffraction pattern of the amorphous alloy melt after cooling to room temperature in Example 1. As shown in the figure, no sharp diffraction peaks appear, indicating that the obtained amorphous alloy has a completely amorphous structure. For the Vit1 alloy, the copper melt shrinkage test mold 12 can provide a sufficient cooling rate. This demonstrates that the apparatus of this embodiment can recreate the amorphous alloy preparation process and can test the shrinkage rate during the transformation of the amorphous alloy melt into an amorphous alloy.

Claims

1. A device for testing the shrinkage rate of amorphous alloy melt based on an optical lever, characterized in that... It consists of a scale (1), a vacuum furnace body (2), an infrared thermometer (3), a K-type thermocouple (6), a lifting bracket (7), a laser generator (9), an induction coil (10), a crucible (11), a melt shrinkage test mold (12), an optical lever bracket (13), an optical lever (14), a thin-film slider bracket (15), and a slider assembly (16); The vacuum furnace body (2) is provided with a flange for monitoring the melt temperature on the top and a rotary dynamic sealing mechanism on the side wall. A transparent window is provided on the furnace door of the vacuum furnace body (2). An infrared thermometer (3) is located outside the vacuum furnace body (2) and directly above the flange for monitoring the melt temperature. The K-type thermocouple (6), lifting bracket (7), induction coil (10), crucible (11), melt shrinkage test mold (12), optical lever bracket (13), optical lever (14), thin-film slider bracket (15) and slider assembly (16) are arranged inside the vacuum furnace body (2); the lifting bracket (7) is arranged at the bottom of the vacuum furnace body (2), and the melt shrinkage test mold (12) is arranged on the lifting bracket (7); The melt shrinkage test mold (12) is internally composed of a pouring cup (12-1), a vertical runner (12-2), a horizontal runner (12-3), and a vertical cavity (12-4) connected in sequence to form a U-shaped structure. The horizontal height of the outlet cross-section of the pouring cup (12-1) is higher than the upper end face of the vertical cavity (12-4). A thin-plate slider bracket (15) is provided on the upper end face of the melt shrinkage test mold (12). The thickness of the thin-plate slider bracket (15) is 0.3mm to 0.8mm. A thermocouple insertion hole is provided on the side of the vertical cavity (12-4). One end of a K-type thermocouple (6) passes through the thermocouple insertion hole and is placed inside the vertical cavity (12-4). A light lever bracket (13) is provided on the side wall of the melt shrinkage test mold (12), and the upper end face of the light lever bracket (13) is on the same horizontal plane as the upper end face of the melt shrinkage test mold (12). The slider assembly (16) consists of a slider (16-1), a connecting rod (16-2), and an overlapping piece (16-3). The slider (16-1) is disposed on the upper part of the vertical cavity (12-4) and is clearance-fitted. The upper end of the slider (16-1) is connected to one end of the connecting rod (16-2). The other end of the connecting rod (16-2) passes through the thin-plate slider bracket (15) and is connected to the overlapping piece (16-3). The overlapping piece (16-3) overlaps the upper surface of the thin-plate slider bracket (15). The optical lever (14) consists of a front foot tip (17), a bracket (18), a reflector (19), a horizontal rod (20), and a horizontal rod foot tip (21). The lower end of the front foot tip (17) is set on the upper end face of the optical lever bracket (13), the horizontal rod foot tip (21) is in contact with the upper end face of the overlapping piece (16-3), and the reflector (19) corresponds to the position of the transparent window on the furnace door of the vacuum furnace body (2). An induction coil (10) is provided outside the crucible (11). The end of the induction coil (10) passes through the rotary dynamic sealing mechanism and is fixed, so that the crucible (11) is positioned directly above the pouring cup (12-1) and simultaneously directly below the flange used for monitoring the melt temperature. The scale (1) is set outside the vacuum furnace body (2), and the scale of the scale (1) corresponds to the position of the transparent window on the furnace door of the vacuum furnace body (2). A laser generator (9) is set between the scale (1) and the transparent window.

2. The device for testing the shrinkage rate of amorphous alloy melt based on an optical lever according to claim 1, characterized in that... A camera (8) is installed on the outside of the vacuum furnace body (2), and the position of the camera (8) corresponds to the scale of the ruler (1).

3. The device for testing the shrinkage rate of amorphous alloy melt based on an optical lever according to claim 1, characterized in that... The side wall of the vacuum furnace body (2) is provided with a flange for thermocouple wiring; the other end of the K-type thermocouple (6) is electrically connected to the temperature data acquisition device (5) through the flange for thermocouple wiring, and the temperature data acquisition device (5) is connected to the computer (4) through an RJ45 interface.

4. The amorphous alloy melt shrinkage rate testing device based on optical lever according to claim 1, characterized in that... The vacuum furnace body (2) is connected to the secondary vacuum system.

5. The amorphous alloy melt shrinkage rate testing device based on optical lever according to claim 1, characterized in that... The pouring cup (12-1) has a conical structure, and the inlet cross-section of the pouring cup (12-1) is larger than the outlet cross-section of the pouring cup (12-1).

6. The amorphous alloy melt shrinkage rate testing device based on optical lever according to claim 1, characterized in that... The vertical runner (12-2), horizontal runner (12-3), and vertical cavity (12-4) are all cylindrical cavity structures; let the diameter of the vertical runner (12-2) and horizontal runner (12-3) be d. C The diameter of the vertical cavity (12-4) is D. C D C ≥d C .

7. The device for testing the shrinkage rate of amorphous alloy melt based on an optical lever according to claim 1, characterized in that... The reflector (19) is mounted on the bracket (18). The bottom of the bracket (18) is provided with a front foot (17). A horizontal rod (20) is provided on one side end face of the bracket (18). A horizontal rod foot (21) is provided at the end of the horizontal rod (20).

8. The method of using the amorphous alloy melt shrinkage rate testing device based on optical lever as described in claim 1, characterized in that... It is done in the following steps:

1. Place the melt shrinkage test mold (12) on the lifting bracket (7), place the amorphous alloy in the crucible (11), then close the vacuum furnace body (2) and evacuate the vacuum, and then introduce argon gas; 2. Turn on the laser generator (9) and position the laser beam directly onto the reflector (19) of the optical lever (14); 3. The amorphous alloy in the crucible (11) is induction melted using an induction coil (10) to obtain an amorphous alloy melt. The temperature of the melt is measured using an infrared thermometer (3) to determine whether it has reached the preset temperature.

4. By rotating the induction coil (10), the amorphous alloy melt in the crucible (11) is cast into the vertical cavity (12-4) of the melt shrinkage test mold (12). The optical lever (14) and the K-type thermocouple (6) both start to respond. The change of the scale corresponding to the laser emitted by the laser generator (9) is recorded by the reflection of the laser mirror (19) on the scale (1). At the same time, the temperature change of the amorphous alloy melt is recorded. The shrinkage amount of the amorphous alloy melt in the vertical cavity (12-4) in the length direction is calculated by formula (a), and converted into the shrinkage rate by formula (b). Then, the corresponding relationship between the shrinkage rate of the amorphous alloy melt and the melt temperature is obtained. In the formula, d is the vertical distance from the front foot (17) of the optical lever (14) to the horizontal rod foot (21), in mm; D is the vertical distance from the reflector (19) of the optical lever (14) to the scale (1), in mm; Δl is the amount of shrinkage of the amorphous alloy melt in the vertical cavity (12-4) in the length direction, in mm; ΔL is the change in the reading of the scale (1) when the amorphous alloy melt shrinks by Δl, in mm; ε is the shrinkage rate of the amorphous alloy melt; l C The initial length of the amorphous alloy melt in the vertical cavity (12-4) is in the longitudinal direction, in mm.

9. The method of using the amorphous alloy melt shrinkage rate testing device based on optical lever according to claim 8, characterized in that... In step four, when the amorphous alloy melt fills the vertical cavity (12-4) and contacts the lower end face of the slider (16-1), the upper end face of the overlapping piece (16-3) rises from the original position 1 to position 2. As the temperature of the amorphous alloy melt decreases, it shrinks and the upper end face of the overlapping piece (16-3) drops to position 3.

10. The amorphous alloy melt shrinkage rate testing device based on optical lever according to claim 9, characterized in step... Formula (a) described in section 4 is derived from formulas (c) to (l), and formula (b) is calculated from formulas (a) and (m), as follows: When θ→0: Then we have: Similarly, we have: When γ→0 Then we have: Therefore: The shrinkage rate of amorphous alloy melt can be calculated by the following formula: L C =l y +Δl0(m) In the formula, d is the vertical distance from the front foot (17) of the optical lever (14) to the horizontal rod foot (21), in mm; D is the vertical distance from the reflector (19) of the optical lever (14) to the scale (1), in mm; ε is the shrinkage rate of the amorphous alloy melt; l C The initial length of the amorphous alloy melt in the vertical cavity (12-4) along its longitudinal direction, in mm; y θ is the distance from the lower end face of the slider (16-1) to the bottom of the vertical cavity (12-4) in the initial state before the amorphous alloy melt enters the vertical cavity (12-4); θ is the angle between the horizontal rod (20) and the horizontal direction when the upper end face of the overlapping piece (16-3) rises from the original position 1 to position 2; Δl0 is the distance from the upper end face of the overlapping piece (16-3) rising from the original position 1 to position 2, in mm; ΔL0 is the change in the reading of the corresponding scale (1) when the upper end face of the overlapping piece (16-3) rises from the original position 1 to position 2, in mm. The position is mm; γ is the angle between the horizontal rod (20) and the horizontal direction when the upper end face of the overlapping piece (16-3) descends from position 2 to position 3; Δl is the amount of shrinkage of the amorphous alloy melt in the vertical cavity (12-4) in the length direction, that is, the distance from the upper end face of the overlapping piece (16-3) descending from position 2 to position 3, in mm; ΔL is the change in the reading of the scale (1) corresponding to the shrinkage of the amorphous alloy melt by Δl, that is, the change in the reading of the scale (1) corresponding to the descending from position 2 to position 3, in mm.

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