A magnesium alloy particle semi-solid temperature range measuring device

Abstract

The utility model relates to magnesium alloy semi -solid injection moulding technical field discloses a magnesium alloy particle semi -solid temperature range measuring device, including support, hot nozzle, apron, temperature measurement unit, stirring unit, heating unit and temperature control unit. Through the observation of the macrostate of the magnesium alloy that falls or drops, without using other precision analytical instrument, can conveniently judge whether magnesium alloy is in semi -solid, and further determine the temperature range of magnesium alloy semi -solid, solve the problem that the technical personnel cannot actually measure the semi -solid temperature range of magnesium alloy particle under the condition that cannot use precision instrument in actual production.

Description

Technical Field

[0001] This utility model relates to the field of magnesium alloy semi-solid injection molding technology, and in particular to a device for measuring the semi-solid temperature range of magnesium alloy particles. Background Technology

[0002] Existing technologies for determining the semi-solid temperature range of magnesium alloys employ methods such as thermal analysis, microstructure observation, temperature measurement and phase diagram comparison, and physical property testing. These methods require sophisticated research equipment or complex development processes, resulting in slow efficiency and high costs. Furthermore, the semi-solid temperature range varies depending on the magnesium alloy's composition. In actual production, technicians rely on production experience and forming data from similar alloys to initially determine a semi-solid temperature range before conducting trial production. This approach can easily lead to poor product forming, structural and performance defects, equipment damage, and safety hazards.

[0003] Therefore, there is an urgent need for a magnesium alloy semi-solid temperature measuring device that can be applied in actual production environments to efficiently and easily obtain the temperature range of magnesium alloy semi-solids, providing a precise molding temperature range for magnesium alloy injection molding. Utility Model Content

[0004] To address the aforementioned shortcomings, the purpose of this invention is to propose a device for measuring the semi-solid temperature range of magnesium alloy particles, thereby solving the problem that technicians cannot conveniently measure the semi-solid temperature range of magnesium alloy particles using a simple device in actual production.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] A semi-solid temperature range measuring device for magnesium alloy particles includes a support, a hot nozzle, a cover plate, a temperature measuring unit, a stirring unit, a heating unit, and a temperature control unit. The hot nozzle is a hollow cylindrical structure with its axis arranged vertically. The hot nozzle has a middle section with a constant inner diameter and a gate with a decreasing inner diameter. The inner diameter A of the middle section is 20~30mm. The gate is located at the bottom of the middle section. The inner diameter of the hot nozzle gradually increases from the bottom of the gate downwards. The distance E between the gate and the bottom of the hot nozzle is 18~22mm. The length L of the hot nozzle is 160~240mm.

[0007] The cover plate is detachably disposed at the bottom of the hot nozzle and is used to close the bottom of the hot nozzle. The temperature measuring part of the temperature measuring unit is disposed at the gate. The stirring unit is used to stir the material to be measured filled in the hot nozzle. The heating unit is used to heat the hot nozzle and the material to be measured filled inside it. The heating unit is electrically connected to the temperature control unit and is used to control the heating power of the heating unit. The bracket is used to fix the hot nozzle, the temperature measuring part of the temperature measuring unit, the stirring unit, and the heating unit.

[0008] Preferably, the outer side of the middle section of the hot nozzle is provided with an annular protrusion, the heating unit adopts a resistance wire heating coil, the heating unit includes a first heating coil and a second heating coil, the first heating coil and the second heating coil are sleeved on the outer side of the hot nozzle, the first heating coil extends upward from the top of the annular protrusion to near the top of the hot nozzle, and the second heating coil extends downward from the bottom of the annular protrusion to the outer side of the gate.

[0009] The temperature control unit includes a controller, a first thermocouple, and a second thermocouple. The first thermocouple is positioned at the middle of the first heating coil along the vertical direction, between the first heating coil and the hot nozzle, and is used to measure the temperature inside the first heating coil. The second thermocouple is positioned at the middle of the second heating coil along the vertical direction, between the second heating coil and the hot nozzle, and is used to measure the temperature inside the second heating coil. The controller is electrically connected to the first heating coil, the second heating coil, the first thermocouple, and the second thermocouple.

[0010] The temperature measuring unit includes a temperature display and a third thermocouple. The third thermocouple is electrically connected to the temperature display and is located at the gate. The temperature display is used to display the measured temperature of the third thermocouple.

[0011] Preferably, it also includes a protective shell, which includes an upper shell and a lower shell. The upper shell is fitted onto the outside of the first heating coil, and the upper side of the upper shell has an inwardly turned flange. The lower shell is fitted onto the outside of the second heating coil, and the lower side of the lower shell has an inwardly turned flange. A gap M of 3-8 mm is provided between the protective shell and the outside of the heating nozzle along the radial direction of the heating nozzle.

[0012] Preferably, the bottom of the hot nozzle is provided with an outer diameter reduction section, the length N of which is 5~10mm, and the inner diameter D of the bottom of the hot nozzle is the same as the inner diameter A of the middle section.

[0013] Preferably, the bracket includes a first support platform, a second support platform, and a plurality of columns. The second support platform is vertically positioned directly below the first support platform. The plurality of columns support the first support platform and the second support platform. The first support platform has a first mounting hole, and the second support platform has a second mounting hole. The first mounting hole and the second mounting hole are coaxially arranged. The hot nozzle passes through the first mounting hole and the second mounting hole.

[0014] The bracket also includes a mounting ring, and the outer periphery of the first mounting hole is provided with a mounting groove that matches the shape of the annular protrusion. The mounting ring is disposed on the upper side of the annular protrusion and the annular protrusion and the mounting groove are locked together by bolts.

[0015] Preferably, it also includes a pull rod and several foot pads, with the foot pads disposed at the bottom of the second support platform. The bottom of the hot nozzle is flush with the bottom plane of the second support platform. A fixed pivot is disposed at the bottom of the second support platform in a vertical direction. One end of the cover plate is rotatably connected to the fixed pivot, and the upper surface of the cover plate is in close contact with the bottom plane of the second support platform. The other end of the cover plate is pivotally connected to the pull rod.

[0016] Preferably, the first support platform and the second support platform are respectively provided with hollow holes, which are respectively provided on the outer periphery of the first mounting hole and the second mounting hole, and the hollow holes are spaced apart along the circumference of the first mounting hole and the second mounting hole.

[0017] Preferably, the support further includes a third support platform, the stirring unit includes a motor and a stirring rod, the stirring rod has several stirring blades evenly distributed on it, the column is also used to support the third support platform, the third support platform is disposed above the first support platform, the motor is fixed to the third support platform, the third support platform is provided with a stirring hole, the stirring rod passes through the stirring hole, one end of the stirring rod is connected to the motor, the other end of the stirring rod extends into the inner cavity of the hot nozzle, and the distance J between the bottom of the stirring rod and the gate is 10~12mm.

[0018] The technical solution provided by this utility model can include the following beneficial effects:

[0019] 1. By observing the macroscopic state of fallen or dripping magnesium alloy, it is possible to conveniently determine whether the magnesium alloy is in a semi-solid state without the need for other precision analytical instruments. This allows for the determination of the semi-solid temperature range of the magnesium alloy, solving the problem of technicians being unable to accurately measure the semi-solid temperature range of magnesium alloy particles in actual production when precision instruments are unavailable. This method efficiently and easily obtains the semi-solid temperature range of magnesium alloys, reducing trial and error, shortening mold-making cycles, saving materials, lowering costs, and avoiding safety hazards.

[0020] 2. Contact between the cover plate and the bottom of the hot nozzle will cause heat loss from the hot nozzle and its internal magnesium alloy, affecting the temperature measurement at the bottom of the hot nozzle. The inner diameter of the hot nozzle decreases at the gate, reducing the cross-sectional area of ​​the inner cavity and minimizing heat loss through heat conduction from the magnesium alloy at the gate. Maintaining a distance E between the gate and the cover plate reduces the impact of heat transfer from the cover plate on the temperature detection at the hot nozzle gate. Ensuring the magnesium alloy and the hot nozzle maintain a consistent temperature at the gate improves measurement accuracy and stability. The length of the hot nozzle should not be too short, leading to uneven heating; too long, it will overload the heating element, affecting detection accuracy. If the hot nozzle diameter is too large, higher heating power is required to maintain the temperature, and it may also cause uneven heating of the magnesium alloy inside the nozzle, resulting in a "hot outside, cold inside" problem. If the hot nozzle diameter is too small, it may lead to excessive heat conduction and localized overheating, causing excessive temperature fluctuations when the temperature control unit controls the temperature, affecting measurement accuracy.

[0021] 3. The middle section of the heating nozzle is provided with an annular protrusion for easy installation. The heating unit adopts a first heating coil and a second heating coil set at the top and bottom respectively. After the temperature is manually set in the input panel of the temperature control unit, the temperature control unit adjusts the power of the first heating coil through the feedback of the first thermocouple and adjusts the power of the second heating coil through the feedback of the second thermocouple, so as to realize independent temperature control of the upper and lower sections of the heating nozzle, ensuring uniform temperature control of the heating nozzle and improving the accuracy and stability of the measurement.

[0022] 4. Add a protective shell to protect and insulate the heating coil. By leaving a gap between the protective shell and the heating nozzle, air insulation is achieved, which further improves the temperature control effect and enhances the accuracy and stability of the measurement.

[0023] 5. By reducing the outer diameter of the hot nozzle bottom, the cross-sectional area of ​​the contact part between the hot nozzle and the cover plate is reduced, thereby reducing the heat transfer between the hot nozzle and the cover plate and reducing the influence of the cover plate on the temperature measurement at the gate, thus further improving the measurement accuracy.

[0024] 6. Fix the cover plate to the bracket to avoid affecting the temperature measurement accuracy when the cover plate is installed on the hot nozzle. Use the pull rod to drive the cover plate to rotate horizontally around the fixed pivot, so as to easily open and close the cover plate and avoid accidental burns from the hot nozzle or falling magnesium alloy when directly operating the cover plate.

[0025] 7. Add perforated holes around the outer periphery of the first and second mounting holes to reduce heat conduction through the first and second support platforms, thereby reducing heat loss and improving temperature control accuracy.

[0026] 8. Keep the bottom of the stirring rod away from the gate to avoid agitation affecting the state of the magnesium alloy at the gate. Attached Figure Description

[0027] Figure 1 This is a cross-sectional view of one embodiment of the present invention.

[0028] Figure 2 This is a partially enlarged cross-sectional view of one embodiment of the present invention.

[0029] Figure 3 This is a three-dimensional structural diagram of one embodiment of the present invention.

[0030] Figure 4 This is a three-dimensional structural schematic diagram of another embodiment of the present invention.

[0031] Figure 5 This is a three-dimensional structural diagram of a heat nozzle according to an embodiment of the present invention.

[0032] The components include: bracket 1, hollow hole 100, first support platform 11, first mounting hole 111, second support platform 12, second mounting hole 121, fixed rotating shaft 122, third support platform 13, feeding port 131, column 14, mounting ring 15, hot nozzle 2, middle section 21, annular protrusion 211, gate 22, outer diameter reduction section 23, temperature measuring hole 24, cover plate 3, temperature measuring unit 4, temperature display 41, third thermocouple 42, stirring unit 5, motor 51, stirring rod 52, heating unit 6, temperature control unit 7, controller 71, first thermocouple 72, second thermocouple 73, upper shell 81, lower shell 82, pull rod 91, and foot pad 92. Detailed Implementation

[0033] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0034] In the description of this utility model, it should be understood that the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this utility model. Furthermore, features defined with "first" and "second" may explicitly or implicitly include one or more of these features, used to distinguish and describe features, without any order or emphasis.

[0035] In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0036] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0037] The embodiments of this utility model are described below with reference to the accompanying drawings.

[0038] A semi-solid temperature range measuring device for magnesium alloy particles includes a support 1, a hot nozzle 2, a cover plate 3, a temperature measuring unit 4, a stirring unit 5, a heating unit 6, and a temperature control unit 7. The hot nozzle 2 is a hollow cylindrical structure with its axis arranged vertically. The hot nozzle 2 has a middle section 21 with a constant inner diameter and a gate 22 with a decreasing inner diameter. The inner diameter A of the middle section 21 is 20~30mm. The gate 22 is located at the bottom of the middle section 21. The inner diameter of the hot nozzle 2 gradually increases from the bottom of the gate 22 downwards. The distance E between the gate 22 and the bottom of the hot nozzle 2 is 18~22mm. The length L of the hot nozzle 2 is 160~240mm.

[0039] The cover plate 3 is detachably disposed at the bottom of the hot nozzle 2, and the cover plate 3 is used to close the bottom of the hot nozzle 2. The temperature measuring part of the temperature measuring unit 4 is disposed at the gate 22. The stirring unit 5 is used to stir the material to be measured filled in the hot nozzle 2. The heating unit 6 is used to heat the hot nozzle 2 and the material to be measured filled inside it. The heating unit 6 is electrically connected to the temperature control unit 7, and the temperature control unit 7 is used to control the heating power of the heating unit 6. The bracket 1 is used to fix the hot nozzle 2, the temperature measuring part of the temperature measuring unit 4, the stirring unit 5 and the heating unit 6.

[0040] like Figure 1 and Figure 2 As shown, the heating unit 6 is controlled by the temperature control unit 7 to slowly heat up the heating nozzle 2 and the magnesium alloy particles to be measured inside it. During the heating process, the cover plate 3 is repeatedly opened to observe whether magnesium alloy particles or molten material fall from the bottom of the heating nozzle 2, and the current temperature displayed by the temperature measuring unit 4 is recorded. If magnesium alloy particles fall out, the current temperature is recorded as the solid temperature of the magnesium alloy. If molten magnesium alloy drips down, the current temperature of the thermometer is recorded as the liquid temperature of the magnesium alloy. If no material falls down, the current temperature is recorded as the semi-solid temperature of the magnesium alloy. Finally, the recorded temperature data is used to plot the heating curve and obtain the semi-solid temperature range of the magnesium alloy particles.

[0041] By observing the macroscopic state of fallen or dripping magnesium alloy, it is possible to conveniently determine whether the magnesium alloy is in a semi-solid state without the need for other precision analytical instruments. This allows for the determination of the semi-solid temperature range of the magnesium alloy, solving the problem of technicians being unable to accurately measure the semi-solid temperature range of magnesium alloy particles in actual production when precision instruments are unavailable. This method efficiently and easily obtains the semi-solid temperature range of magnesium alloys, reducing trial and error, shortening mold-making cycles, saving materials, lowering costs, and avoiding safety hazards.

[0042] Contact between the cover plate 3 and the bottom of the hot nozzle 2 will cause heat loss from the hot nozzle 2 and its internal magnesium alloy, affecting the temperature measurement at the bottom of the hot nozzle 2. The inner diameter of the hot nozzle 2 decreases at the gate 22, reducing the cross-sectional area of ​​the inner cavity of the hot nozzle 2 at the gate 22 and reducing the heat loss from the magnesium alloy through heat conduction at the gate 22. Maintaining a distance E between the gate 22 and the cover plate 3 reduces the impact of heat transfer from the cover plate 3 on the temperature detection at the gate 22 of the hot nozzle 2. Ensuring that the magnesium alloy and the hot nozzle 2 maintain the same temperature at the gate 22 improves the accuracy and stability of temperature measurement. The length of the hot nozzle 2 should not be too short, as this will lead to uneven heating; if it is too long, the heating unit 6 will operate under overload, affecting the detection accuracy. If the diameter of the hot nozzle 2 is too large, higher heating power is required to maintain the temperature, and it may also cause uneven heating of the magnesium alloy inside the hot nozzle 2, resulting in a "hot outside, cold inside" problem; if the diameter of the hot nozzle 2 is too small, it may lead to excessive heat conduction and localized overheating, causing excessive fluctuations in the temperature control unit 7 when controlling the temperature, affecting the measurement accuracy.

[0043] In a specific embodiment, the hot nozzle 2 uses the same material and dimensions as the injection molding machine nozzle, making the temperature rise curve of the semi-solid temperature range closer to the actual production environment and more valuable for reference. The hot nozzle 2 is made of Mo-50W tungsten-molybdenum alloy, which is high-temperature resistant and has a thermal conductivity greater than 100W / (m•K) at 500℃. The hot nozzle 2 heats up quickly and maintains a uniform temperature. The cover plate 3 is made of 1.2888 steel, which is also high-temperature resistant.

[0044] Preferably, the wall thickness K of the middle section 21 is 8~12mm. This avoids situations where the wall thickness is too thin, resulting in insufficient rigidity of the hot nozzle and easy deformation during long-term use; conversely, if the wall thickness is too thick, the heat transfer efficiency of the hot nozzle decreases, the magnesium alloy filling the hot nozzle is heated unevenly, and the temperature control efficiency decreases.

[0045] Preferably, the outer side of the middle section 21 of the hot nozzle 2 is provided with an annular protrusion 211, the heating unit 6 adopts a resistance wire heating coil, the heating unit 6 includes a first heating coil and a second heating coil, the first heating coil and the second heating coil are sleeved on the outer side of the hot nozzle 2, the first heating coil extends upward from the top of the annular protrusion 211 to near the top of the hot nozzle 2, and the second heating coil extends downward from the bottom of the annular protrusion 211 to the outer side of the gate 22;

[0046] The temperature control unit 7 includes a controller 71, a first thermocouple 72, and a second thermocouple 73. The first thermocouple 72 is positioned at the middle of the first heating coil along the vertical direction, between the first heating coil and the hot nozzle 2, and is used to measure the temperature inside the first heating coil. The second thermocouple 73 is positioned at the middle of the second heating coil along the vertical direction, between the second heating coil and the hot nozzle 2, and is used to measure the temperature inside the second heating coil. The controller 71 is electrically connected to the first heating coil, the second heating coil, the first thermocouple 72, and the second thermocouple 73.

[0047] The temperature measuring unit 4 includes a temperature display 41 and a third thermocouple 42. The third thermocouple 42 is electrically connected to the temperature display 42 and is located at the gate 22. The temperature display 41 is used to display the measured temperature of the third thermocouple 42.

[0048] The middle section 21 of the heating nozzle 2 is provided with an annular protrusion 211 for easy installation. The heating unit 6 adopts a first heating coil and a second heating coil respectively set at the top and bottom. After the temperature is manually set in the input panel of the temperature control unit 7, the temperature control unit 7 adjusts the power of the first heating coil through the feedback of the first thermocouple 72 and adjusts the power of the second heating coil through the feedback of the second thermocouple 73, so as to realize independent temperature control of the upper and lower sections of the heating nozzle 2, ensuring uniform temperature control of the heating nozzle 2 and improving the accuracy and stability of the measurement.

[0049] like Figure 5 As shown, preferably, the outer side of the hot nozzle 2 is provided with a plurality of temperature measuring holes 24. These holes 24 are used to insert the first thermocouple 72, the second thermocouple 73, and the third thermocouple 42 into the holes without obstruction. The first thermocouple 72, the second thermocouple 73, and the third thermocouple 42 are arranged in pairs. Inserting the first thermocouple 72, the second thermocouple 73, and the third thermocouple 42 into the temperature measuring holes 24 makes the measured temperature closer to the actual temperature of the magnesium alloy inside the hot nozzle 2. The paired arrangement reduces temperature measurement error and improves measurement accuracy.

[0050] Preferably, it also includes a protective shell, which includes an upper shell 81 and a lower shell 82. The upper shell 81 is sleeved on the outside of the first heating coil, and the upper side of the upper shell 81 has an inward flange. The lower shell 82 is sleeved on the outside of the second heating coil, and the lower side of the lower shell 82 has an inward flange. A gap M of 3~8mm is provided between the protective shell and the outer side of the heating nozzle 2 along the radial direction of the heating nozzle 2.

[0051] Adding a protective shell protects and insulates the heating coil. By leaving a gap between the protective shell and the heating nozzle 2, air insulation is achieved, further improving the temperature control effect and enhancing the accuracy and stability of the measurement.

[0052] Preferably, the protective shell is made of stainless steel. Stainless steel is sturdy, durable, and has good thermal stability.

[0053] Preferably, the bottom of the hot nozzle 2 is provided with an outer diameter reduction section 23, the length N of the outer diameter reduction section 23 is 5~10mm, and the inner diameter D of the bottom of the hot nozzle 2 is the same as the inner diameter A of the middle section 21.

[0054] By reducing the outer diameter of the bottom of the hot nozzle 2, the cross-sectional area of ​​the contact part between the hot nozzle 2 and the cover plate 3 is reduced, thereby reducing the heat transfer between the hot nozzle 2 and the cover plate 3 and reducing the influence of the cover plate 3 on the temperature measurement at the gate 22, the measurement accuracy is further improved.

[0055] Preferably, the bracket 1 includes a first support platform 11, a second support platform 12, and a plurality of columns 14. The second support platform 12 is vertically positioned directly below the first support platform 11. The plurality of columns 14 are used to support the first support platform 11 and the second support platform 12. The first support platform 11 is provided with a first mounting hole 111, and the second support platform 12 is provided with a second mounting hole 121. The first mounting hole 111 and the second mounting hole 121 are coaxially arranged. The hot nozzle 2 passes through the first mounting hole 111 and the second mounting hole 121.

[0056] The bracket 1 also includes a mounting ring 15. The outer periphery of the first mounting hole 111 is provided with a mounting groove that matches the shape of the annular protrusion 211. The mounting ring 15 is disposed on the upper side of the annular protrusion 211 and the annular protrusion 211 and the mounting groove are locked together by bolts.

[0057] like Figure 3 and Figure 4 As shown, the hot nozzle 2 is installed and fixed through the first mounting hole 111, the second mounting hole 121, the mounting ring 15 and the mounting groove to prevent the hot nozzle 2 from being accidentally displaced during operation.

[0058] Preferably, it also includes a pull rod 91 and a plurality of foot pads 92, the plurality of foot pads 92 being disposed at the bottom of the second support platform 12, the bottom of the hot nozzle 2 being flush with the bottom plane of the second support platform 12, a fixed rotating shaft 122 being disposed at the bottom of the second support platform 12 in a vertical direction, one end of the cover plate 3 being horizontally rotatably connected to the fixed rotating shaft 122, and the upper surface of the cover plate 3 being in close contact with the bottom plane of the second support platform 12, and the other end of the cover plate 3 being pivotally connected to the pull rod 91.

[0059] The cover plate 3 is fixed to the bracket 1 to avoid affecting the temperature measurement accuracy when the cover plate 3 is installed on the hot nozzle 2. The pull rod 91 drives the cover plate 3 to rotate horizontally around the fixed rotating shaft 122, making it easy to open and close the cover plate 3 and avoiding accidental burns from the hot nozzle 2 or falling magnesium alloy when directly operating the cover plate 3.

[0060] Preferably, the first support platform 11 and the second support platform 12 are respectively provided with hollow holes 100. The hollow holes 100 are respectively provided on the outer periphery of the first mounting hole 111 and the second mounting hole 121, and the hollow holes 100 are spaced apart along the circumference of the first mounting hole 111 and the second mounting hole 121.

[0061] Hole holes 100 are added to the outer periphery of the first mounting hole 111 and the second mounting hole 121 to reduce heat conduction through the first support platform 11 and the second support platform 12, thereby reducing heat loss and improving temperature control accuracy.

[0062] Preferably, the bracket 1 further includes a third support platform 13, the stirring unit 5 includes a motor 51 and a stirring rod 52, the stirring rod 52 has a plurality of stirring blades evenly distributed on it, the column 14 is also used to support the third support platform 13, the third support platform 13 is disposed above the first support platform 11, the motor 51 is fixed to the third support platform 13, the third support platform 13 is provided with a stirring hole, the stirring rod 52 passes through the stirring hole, one end of the stirring rod 52 is connected to the motor 51, the other end of the stirring rod 52 extends into the inner cavity of the hot nozzle 2, and the distance J between the bottom of the stirring rod 52 and the gate 22 is 10~12mm.

[0063] Generally, magnesium alloy particles have a particle size between 50 and 500 micrometers. A stirring rod 52 with impellers can effectively agitate the magnesium alloy particles. The bottom of the stirring rod 52 is kept at a distance from the gate 22 to avoid affecting the state of the magnesium alloy at the gate 22.

[0064] Preferably, the top of the hot nozzle 2 is provided with a feeding section, the inner diameter of which gradually increases from bottom to top, the inner diameter of the bottom of the feeding section is the same as the inner diameter of the middle section 21, and the inner diameter B of the top of the feeding section is twice the inner diameter A of the middle section 21; the third support platform 13 is provided with a feeding port 131, which is used to prevent air from entering, so as to facilitate the addition of magnesium alloy particles and observation.

[0065] A method for measuring the semi-solid temperature range of magnesium alloy particles, using the aforementioned measuring device, includes the following operating steps:

[0066] Step 1: Fill the inner cavity of the hot nozzle 2 with the magnesium alloy particles to be measured, and input the estimated value of the semi-solid temperature of the magnesium alloy particles to be measured.

[0067] Step 2: The heating unit 6 is heated by the temperature control unit 7, and the stirring unit 5 is turned on to keep stirring.

[0068] Step 3: When the temperature of the hot nozzle 2 is close to the estimated value, adjust the temperature control unit 7 to keep the temperature constant;

[0069] Step 4: Open cover plate 3 to observe whether magnesium alloy particles or molten magnesium alloy fall out. If magnesium alloy particles fall out, close cover plate 3, record the current temperature of temperature measuring unit 4 as the solid temperature, replenish magnesium alloy solid particles from the top of hot nozzle 2, and proceed to step 5; if molten magnesium alloy drips out, or no material falls out, it is determined that the estimated value needs to be reduced, stop the measurement, wait for hot nozzle 2 to cool down, and return to step 1 to measure again.

[0070] Step 5: Adjust the temperature control unit 7 to raise the temperature;

[0071] Step Six: After the temperature stabilizes, open the cover plate 3 again to observe whether magnesium alloy particles or molten magnesium alloy fall out. If magnesium alloy particles fall out, close the cover plate 3, record the current temperature of the temperature measuring unit 4 as the solid temperature, and replenish the magnesium alloy solid particles; if no material falls out, keep the cover plate 3 open, record the current temperature of the temperature measuring unit 4 as the semi-solid temperature; if molten magnesium alloy drips out, record it as the liquid temperature, and stop heating and measurement.

[0072] Step 7: Repeat steps 5 and 6 to plot a time-temperature graph based on the recorded temperature data. The temperature range between the lowest and highest semi-solid temperatures recorded is the semi-solid temperature range of the magnesium alloy particles.

[0073] In a specific embodiment, the semi-solid temperature of the magnesium alloy particles is first estimated based on their composition, such as 600°C for AZ91D magnesium alloy and 525°C for AZ80 magnesium alloy. The estimated value of the semi-solid temperature of the magnesium alloy particles to be measured is then input. Based on the surface gloss change of the magnesium alloy at gate 22 and the softening of the magnesium alloy, it can be determined whether the temperature is close to the semi-solid temperature, and the heating rate can be adjusted appropriately to shorten the measurement time.

[0074] By operating lever 91 to open cover plate 3 during the heating process, it can be observed whether the magnesium alloy has reached a semi-solid state. During the heating process, when the temperature exceeds the lower limit of the semi-solid temperature range, the magnesium alloy particles change from solid particles to a semi-solid state with higher viscosity. At this point, the semi-solid magnesium alloy with higher viscosity will not drip from gate 22. The temperature continues to rise until the magnesium alloy finally becomes a liquid with lower viscosity. The viscosity of the liquid magnesium alloy is much lower than that of the semi-solid state, and the liquid magnesium alloy will drip from gate 22. At this point, it is determined that the upper limit of the semi-solid range of the magnesium alloy has been exceeded, and the heating can be stopped to end the measurement.

[0075] Preferably, in step five, the temperature is increased by 5~20℃ each time, and in step six, the cover plate 3 is opened for observation after waiting for 1 minute.

[0076] If the heating rate is less than 5℃ / min, the detection cycle is too long; if the heating rate is greater than 20℃ / min, the temperature fluctuation is too large, making it impossible to accurately observe the state of the magnesium alloy and affecting the measurement accuracy.

[0077] Preferably, the method also includes an error verification step, in which the calibration thermocouple is inserted from the bottom of the hot nozzle into the magnesium alloy particles or magnesium alloy melt at the gate 22 by opening the cover plate, the actual temperature of the magnesium alloy is measured, and the current displayed temperature of the temperature measuring unit 4 is manually adjusted to be equal to the actual temperature to calibrate the temperature measuring unit 4, thereby further improving the accuracy of the measurement structure.

[0078] Other configurations and operations according to the embodiments of this utility model are known to those skilled in the art and will not be described in detail here.

[0079] In this specification, the terms "embodiment," "example," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0080] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A device for measuring the semi-solid temperature range of magnesium alloy particles, characterized in that: The device includes a support, a hot nozzle, a cover plate, a temperature measuring unit, a stirring unit, a heating unit, and a temperature control unit. The hot nozzle is a hollow cylindrical structure with its axis arranged vertically. The hot nozzle has a middle section with a constant inner diameter and a gate with a decreasing inner diameter. The inner diameter A of the middle section is 20~30mm. The gate is located at the bottom of the middle section. The inner diameter of the hot nozzle gradually increases from the bottom of the gate downwards. The distance E between the gate and the bottom of the hot nozzle is 18~22mm. The length L of the hot nozzle is 160~240mm. The cover plate is detachably disposed at the bottom of the hot nozzle and is used to close the bottom of the hot nozzle. The temperature measuring part of the temperature measuring unit is disposed at the gate. The stirring unit is used to stir the material to be measured filled in the hot nozzle. The heating unit is used to heat the hot nozzle and the material to be measured filled inside it. The heating unit is electrically connected to the temperature control unit and is used to control the heating power of the heating unit. The bracket is used to fix the hot nozzle, the temperature measuring part of the temperature measuring unit, the stirring unit, and the heating unit.

2. The device for measuring the semi-solid temperature range of magnesium alloy particles according to claim 1, characterized in that: The hot nozzle has an annular protrusion on the outer side of the middle section. The heating unit adopts a resistance wire heating coil. The heating unit includes a first heating coil and a second heating coil. The first heating coil and the second heating coil are sleeved on the outer side of the hot nozzle. The first heating coil extends upward from the top of the annular protrusion to near the top of the hot nozzle, and the second heating coil extends downward from the bottom of the annular protrusion to the outer side of the gate. The temperature control unit includes a controller, a first thermocouple, and a second thermocouple. The first thermocouple is positioned at the middle of the first heating coil along the vertical direction, between the first heating coil and the hot nozzle, and is used to measure the temperature inside the first heating coil. The second thermocouple is positioned at the middle of the second heating coil along the vertical direction, between the second heating coil and the hot nozzle, and is used to measure the temperature inside the second heating coil. The controller is electrically connected to the first heating coil, the second heating coil, the first thermocouple, and the second thermocouple. The temperature measuring unit includes a temperature display and a third thermocouple. The third thermocouple is electrically connected to the temperature display and is located at the gate. The temperature display is used to display the measured temperature of the third thermocouple.

3. The device for measuring the semi-solid temperature range of magnesium alloy particles according to claim 2, characterized in that: It also includes a protective shell, which comprises an upper shell and a lower shell. The upper shell is fitted onto the outside of the first heating coil, and the upper side of the upper shell has an inwardly turned flange. The lower shell is fitted onto the outside of the second heating coil, and the lower side of the lower shell has an inwardly turned flange. A gap M of 3-8 mm is provided between the protective shell and the outside of the heating nozzle along the radial direction of the heating nozzle.

4. The device for measuring the semi-solid temperature range of magnesium alloy particles according to claim 2, characterized in that: The bottom of the hot nozzle has an outer diameter reduction section, the length N of which is 5~10mm, and the inner diameter D of the bottom of the hot nozzle is the same as the inner diameter A of the middle section.

5. The device for measuring the semi-solid temperature range of magnesium alloy particles according to claim 2, characterized in that: The bracket includes a first support platform, a second support platform, and several columns. The second support platform is vertically positioned directly below the first support platform. The several columns support the first support platform and the second support platform. The first support platform has a first mounting hole, and the second support platform has a second mounting hole. The first mounting hole and the second mounting hole are coaxially arranged. The hot nozzle passes through the first mounting hole and the second mounting hole. The bracket also includes a mounting ring, and the outer periphery of the first mounting hole is provided with a mounting groove that matches the shape of the annular protrusion. The mounting ring is disposed on the upper side of the annular protrusion and the annular protrusion and the mounting groove are locked together by bolts.

6. The device for measuring the semi-solid temperature range of magnesium alloy particles according to claim 5, characterized in that: It also includes a pull rod and several foot pads, with the foot pads disposed at the bottom of the second support platform. The bottom of the hot nozzle is flush with the bottom plane of the second support platform. A fixed pivot is disposed at the bottom of the second support platform in a vertical direction. One end of the cover plate is rotatably connected to the fixed pivot, and the upper surface of the cover plate is in close contact with the bottom plane of the second support platform. The other end of the cover plate is pivotally connected to the pull rod.

7. The device for measuring the semi-solid temperature range of magnesium alloy particles according to claim 5, characterized in that: The first support platform and the second support platform are respectively provided with hollow holes, which are respectively provided on the outer periphery of the first mounting hole and the second mounting hole, and the hollow holes are spaced apart along the circumference of the first mounting hole and the second mounting hole.

8. The device for measuring the semi-solid temperature range of magnesium alloy particles according to claim 5, characterized in that: The support also includes a third support platform. The stirring unit includes a motor and a stirring rod. Several stirring blades are evenly distributed on the stirring rod. The column is also used to support the third support platform. The third support platform is located above the first support platform. The motor is fixed to the third support platform. The third support platform is provided with a stirring hole. The stirring rod passes through the stirring hole. One end of the stirring rod is connected to the motor. The other end of the stirring rod extends into the inner cavity of the hot nozzle. The distance J between the bottom of the stirring rod and the gate is 10~12mm.

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