Material high-temperature temperature field implementation method and system based on laser-assisted heating

Abstract

The invention discloses a method and a system for realizing a high-temperature temperature field of a material based on laser-assisted heating. The method comprises the following steps of: prefabricating speckles with proper size, certain density and random degree on the surface of a tested piece; the test piece is tightly attached to the graphite plate in a mode of drilling holes in the graphite plate; fixing the test piece on the clamp through a pin, and closing the furnace door; vacuumizing the high-temperature furnace through a mechanical pump and a diffusion pump until the high-temperature furnace is close to a vacuum state; resistance wire heating is started, and resistance wire input current is slowly increased; when the temperature of the high-temperature furnace reaches 700 DEG C, a heat preservation state is set, and the control cabinet can automatically set the current to maintain the current temperature; starting a laser to start auxiliary heating, setting the output power to be 1%, increasing the power after the laser is stable, increasing the power by not more than 5% every time, and when the power is increased to 41%, enabling the temperature of the test piece to reach 1200 DEG C; and starting a tensile experiment, and measuring speckle deformation on the surface of the test piece through non-contact measurement equipment to obtain test piece deformation data.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-temperature mechanical property parameter determination of materials, and in particular to a method and system for realizing a high-temperature temperature field of a material based on laser-assisted heating. Background Art

[0002] The determination and characterization of high-temperature mechanical properties of materials are crucial to ensure the thermal stability of aerospace vehicles and improve their overall performance. When aerospace vehicles reenter the atmosphere or perform high-speed flight missions, the high-temperature alloy materials of the spacecraft shell may soften, creep or even melt at high temperatures, affecting the structural stability and safety of the spacecraft. Therefore, the study of high-temperature mechanical properties of materials is of great significance for the optimization design and digital analysis of spacecraft. The various mechanical properties of materials can be measured through high-temperature static tensile tests. The traditional method of heating specimens is to use high-temperature furnace resistance wire heating. Before heating, the high-temperature furnace is first vacuumed by a mechanical pump and an oil diffusion pump to prevent high-temperature oxidation of the specimen and the resistance wire. However, there are pain points in resistance wire heating. When the current is too large, the high-temperature furnace may be disconnected for power protection. The resistance wire heating temperature limit is 1000°C. It is difficult to reach a higher temperature, and additional auxiliary heating equipment is required to heat it up. Summary of the invention

[0003] In order to solve the above technical problems, the present invention proposes a method and system for realizing a high-temperature temperature field of a material based on laser-assisted heating, so as to achieve the purpose of uniformity of the high-temperature temperature field of a material test piece.

[0004] On the one hand, to achieve the above-mentioned purpose, the present invention provides a method for realizing a high-temperature temperature field of a material based on laser-assisted heating, comprising:

[0005] Step 1: Prefabricate speckles of appropriate size, density and randomness on the surface of the test piece;

[0006] Step 2: A graphite plate with a length, width and thickness of 100 mm × 80 mm × 3 mm was made. Since the melting point of iron wire is as high as about 1530°C, a 1 mm iron wire was used to make the specimen fit closely with the graphite plate by drilling holes in the graphite plate;

[0007] Step 3: Fix the test piece on the fixture with pins and close the furnace door;

[0008] Step 4: Use a mechanical pump and a diffusion pump to evacuate the high temperature furnace until it is close to a vacuum state;

[0009] Step 5: Start heating the resistance wire and slowly increase the resistance wire input current to prevent circuit breaker protection;

[0010] Step 6: When the temperature of the high-temperature furnace reaches 700°C, set the insulation state, and the control cabinet will automatically adjust the current to maintain the current temperature;

[0011] Step 7. Turn on the laser to start auxiliary heating. Set the output power to 1% at the beginning. After three minutes, wait for the laser to stabilize and then increase the power. Each increase should not exceed 5%. When the power increases to 41%, the temperature of the specimen reaches 1200℃.

[0012] Step 8: Start the tensile test plan, measure the speckle deformation on the specimen surface through non-contact measurement equipment, and obtain the specimen deformation data.

[0013] On the other hand, to achieve the above-mentioned purpose, the present invention also provides a material high-temperature temperature field realization system based on laser-assisted heating, including: a laser-assisted heating subsystem and a high-temperature furnace overall heating subsystem; wherein, the laser-assisted heating subsystem is composed of a laser lens 9, a fiber laser 10, a laser lens cooling module 11, a laser cooling module 12, and a computer 13 equipped with laser control software, and the lens chiller and the laser chiller are connected to the laser lens 9 and the fiber laser 10 through water pipes to maintain their surface temperature and prevent internal components from burning out, and the control software is connected to the fiber laser 10 through a USB to adjust the heating power to achieve the purpose of controlling the temperature. The graphite plate 6 and the specimen 2 are fastened together by an iron wire, and the laser irradiates the graphite plate to expand the heating area, thereby heating the test area of ​​the specimen 2; the overall heating subsystem of the high-temperature furnace is composed of a resistance wire 1, a high-temperature furnace cold water circulation 3, a clamp 4, a temperature measuring B couple 5, an oil diffusion pump 7 and a mechanical pump 8. The resistance wire 1 is embedded in the high-temperature inner wall, the high-temperature furnace cold water circulation 3 maintains the outer wall of the high-temperature furnace at a normal temperature, the temperature measuring B couple 5 is in contact with the specimen 2 for measuring the temperature, the mechanical pump 8 and the oil diffusion pump 7 are connected to the high-temperature furnace through a pipeline, and the combined work can achieve a vacuum environment inside the high-temperature furnace and prevent high-temperature oxidation of the specimen, and the specimen 2 and the clamp 4 are connected by pins.

[0014] Optionally, the fiber laser model is YDFL-2000-CW-915, and the rated output power is 2000W.

[0015] Optionally, the laser lens cooling module (11) comprises: a lens water chiller connected to the laser lens (9) via a pipeline.

[0016] Optionally, the laser cooling module (12) includes: a laser water chiller connected to the optical fiber laser (10) via a pipeline.

[0017] Optionally, the high temperature furnace cold water circulation 3 includes: an industrial chiller connected to the high temperature furnace through a pipeline.

[0018] Technical effect of the invention: The present invention discloses a method and system for realizing a high-temperature temperature field of a material based on laser-assisted heating, which is applied to realizing a uniform temperature field in a high-temperature mechanical property test area of ​​the material. The test piece is heated as a whole based on a spiral resistance wire in a high-temperature furnace, and an array-type fiber laser is used to directly irradiate a graphite plate through an observation window on the back of the high-temperature furnace. The graphite plate absorbs laser energy and expands the heating area, and thermal radiation makes the temperature field in the test area of ​​the test piece uniform. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0020] Figure 1 It is a schematic flow chart of a method for realizing a high-temperature temperature field of a material based on laser-assisted heating according to an embodiment of the present invention;

[0021] Figure 2 Schematic diagram of the structure of a system for realizing a high-temperature temperature field of a material based on laser-assisted heating according to an embodiment of the present invention, wherein 1 is a resistance wire, 2 is a test piece, 3 is a high-temperature furnace cold water circulation, 4 is a fixture, 5 is a temperature measuring B couple, 6 is a graphite plate, 7 is an oil diffusion pump, 8 is a mechanical pump, 9 is a laser lens, 10 is a fiber laser, 11 is a laser lens cooling module, 12 is a laser cooling module, and 13 is a computer equipped with laser control software. DETAILED DESCRIPTION

[0022] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0023] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0024] like Figure 1 As shown, this embodiment provides a method for realizing a high temperature field of a material based on laser-assisted heating, including:

[0025] Step 1: Prefabricate speckles of appropriate size, density and randomness on the surface of the test piece;

[0026] Step 2: A graphite plate with a length, width and thickness of 100 mm × 80 mm × 3 mm was made. Since the melting point of iron wire is as high as about 1530°C, a 1 mm iron wire was used to make the specimen fit closely with the graphite plate by drilling holes in the graphite plate;

[0027] Step 3: Fix the test piece on the fixture with pins and close the furnace door;

[0028] Step 4: Use a mechanical pump and a diffusion pump to evacuate the high temperature furnace until it is close to a vacuum state;

[0029] Step 5: Start heating the resistance wire and slowly increase the resistance wire input current to prevent circuit breaker protection;

[0030] Step 6: When the temperature of the high-temperature furnace reaches 700°C, set the insulation state, and the control cabinet will automatically adjust the current to maintain the current temperature;

[0031] Step 7. Turn on the laser to start auxiliary heating. Set the output power to 1% at the beginning. After three minutes, wait for the laser to stabilize and then increase the power. Each increase should not exceed 5%. When the power increases to 41%, the temperature of the specimen reaches 1200℃.

[0032] Step 8: Start the tensile test plan, measure the speckle deformation on the specimen surface through non-contact measurement equipment, and obtain the specimen deformation data.

[0033] like Figure 2 As shown, this embodiment also provides a material high temperature field realization system based on laser assisted heating, including: a laser assisted heating subsystem and a high temperature furnace overall heating subsystem; wherein the laser assisted heating subsystem is composed of a laser lens 9, a fiber laser 10, a laser lens cooling module 11, a laser cooling module 12 and a computer 13 equipped with laser control software, the lens chiller and the laser chiller are connected to the laser lens 9 and the fiber laser 10 through water pipes to maintain their surface temperature and prevent internal components from burning out, and the control software is connected to the fiber laser 10 through a USB to adjust the heating power to achieve temperature control The graphite plate 6 and the specimen 2 are fastened together by an iron wire, and the laser irradiates the graphite plate to expand the heating area, thereby heating the test area of ​​the specimen 2; the overall heating subsystem of the high-temperature furnace is composed of a resistance wire 1, a cold water circulation 3, a fixture 4, a temperature measuring B couple 5, an oil diffusion pump 7 and a mechanical pump 8. The resistance wire 1 is embedded in the high-temperature inner wall, and the high-temperature furnace cold water circulation 3 maintains the outer wall of the high-temperature furnace at a normal temperature. The temperature measuring B couple 5 is in contact with the specimen 2 for measuring the temperature. The mechanical pump 8 and the oil diffusion pump 7 are connected to the high-temperature furnace through a pipeline. The combined work can achieve a vacuum environment inside the high-temperature furnace and prevent high-temperature oxidation of the specimen. The specimen 2 and the fixture 4 are connected by a pin.

[0034] The resistance wire 1 is made of iron-chromium-nickel alloy wire, which has the characteristics of high resistivity and strong oxidation resistance. The resistance wire 1 is spirally embedded in the insulation board in the high-temperature furnace and surrounds the entire furnace cavity on all four sides; the insulation board is made of corundum mullite material, which has the characteristics of high heat resistance, good heat insulation, and corrosion resistance. It is stacked on the six sides of the furnace cavity to achieve heat insulation and heat preservation effects. The heating mechanism of the high-temperature furnace is based on the Joule effect generated when current flows through the metal resistance wire, thereby generating heat. Subsequently, this heat is transferred to the test piece by thermal radiation to increase its temperature. This heating method is classified as indirect heating. The resistance wire 1 is evenly arranged on the front, back, left and right sides of the furnace cavity. After the resistance wire 1 is energized, a thermal effect occurs and begins to generate heat and temperature rise. The temperature field in the furnace cavity is approximately a uniform temperature field, which avoids uneven heating of the material test piece.

[0035] Since the maximum temperature of the high-temperature furnace is limited, the laser-assisted heating subsystem uses a fiber laser 10 to locally heat the test area of ​​the specimen 2. The fiber laser used is a model YDFL-2000-CW-915 produced by China Electronics Technology Group Corporation Tianzhixing, with a rated output power of 2000W. Since the laser directly irradiates the specimen, it is very easy to burn the surface of the specimen 2, so a graphite plate is used to indirectly transfer heat to the specimen 2, so that the test area of ​​the specimen 2 reaches a uniform temperature field. A laser lens is set up on the back of the high-temperature furnace, and the laser beam irradiates the specimen in the high-temperature furnace through the observation window, thereby achieving the effect of auxiliary heating.

[0036] The high temperature furnace is integrated with a tensile loading system. When the temperature reaches the required level, the tensile test plan can be implemented through the tensile testing machine control software. The fixture 4 is made of high temperature molybdenum alloy with a melting point of up to 2600°C. It has high strength and low thermal expansion coefficient at high temperatures, ensuring stability and reliability during loading.

[0037] The present invention discloses a method and system for realizing a high-temperature temperature field of a material based on laser-assisted heating, which is applied to realizing a uniform temperature field in a high-temperature mechanical property test area of ​​the material. The test piece is heated as a whole based on a spiral resistance wire in a high-temperature furnace, and an array-type fiber laser is used to directly irradiate a graphite plate through an observation window on the back of the high-temperature furnace. The graphite plate absorbs laser energy and expands the heating area, and the thermal radiation makes the temperature field in the test area of ​​the test piece uniform.

[0038] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for realizing a high temperature field of a material based on laser-assisted heating, characterized in that: include: Step 1: Prefabricate speckles of appropriate size, density and randomness on the surface of the test piece; Step 2: A graphite plate with a length, width and thickness of 100 mm × 80 mm × 3 mm was made. Since the melting point of iron wire is as high as about 1530°C, a 1 mm iron wire was used to make the specimen fit closely with the graphite plate by drilling holes in the graphite plate; Step 3: Fix the test piece on the fixture with pins and close the furnace door; Step 4: Use a mechanical pump and a diffusion pump to evacuate the high temperature furnace until it is close to a vacuum state; Step 5: Start heating the resistance wire and slowly increase the resistance wire input current to prevent circuit breaker protection; Step 6: When the temperature of the high-temperature furnace reaches 700°C, set the insulation state, and the control cabinet will automatically adjust the current to maintain the current temperature; Step 7. Turn on the laser to start auxiliary heating. Set the output power to 1% at the beginning. After three minutes, wait for the laser to stabilize and then increase the power. Each increase should not exceed 5%. When the power increases to 41%, the temperature of the specimen reaches 1200℃. Step 8: Start the tensile test plan, measure the speckle deformation on the specimen surface through non-contact measurement equipment, and obtain the specimen deformation data.

2. A material high temperature field realization system based on laser assisted heating, characterized in that: The system is used to implement the method for realizing a high-temperature temperature field of a material based on laser-assisted heating according to claim 1, and comprises: A laser-assisted heating subsystem and a high-temperature furnace overall heating subsystem; wherein the laser-assisted heating subsystem is composed of a laser lens (9), a fiber laser (10), a laser lens cooling module (11), a laser cooling module (12) and a computer (13) equipped with laser control software; a lens chiller and a laser chiller are connected to the laser lens (9) and the fiber laser (10) through water pipes to maintain their surface temperature and prevent internal components from burning out; the control software is connected to the fiber laser (10) through a USB to adjust the heating power to achieve the purpose of controlling the temperature; a graphite plate (6) and a test piece (2) are fastened together by iron wire; the laser irradiates the graphite plate to expand the graphite plate; The large heating area heats up the test area of ​​the test piece (2); the overall heating subsystem of the high-temperature furnace is composed of a resistance wire (1), a high-temperature furnace cold water circulation (3), a fixture (4), a temperature measuring B couple (5), an oil diffusion pump (7) and a mechanical pump (8); the resistance wire (1) is embedded in the high-temperature inner wall; the high-temperature furnace cold water circulation (3) maintains the outer wall of the high-temperature furnace at a normal temperature; the temperature measuring B couple (5) contacts the test piece (2) for measuring the temperature; the mechanical pump (8) and the oil diffusion pump (7) are connected to the high-temperature furnace through a pipeline; the combined operation can achieve a vacuum environment inside the high-temperature furnace and prevent the test piece from being oxidized at high temperature; the test piece (2) and the fixture (4) are connected by a pin.

3. The material high temperature field realization system based on laser assisted heating according to claim 2, characterized in that: The fiber laser model is YDFL-2000-CW-915, and the rated output power is 2000W.

4. The material high temperature field realization system based on laser assisted heating according to claim 2, characterized in that: The laser lens cooling module (11) comprises: a lens water chiller connected to the laser lens (9) via a pipeline.

5. The material high temperature field realization system based on laser assisted heating according to claim 2, characterized in that: The laser cooling module (12) comprises: a laser water chiller connected to the optical fiber laser (10) via a pipeline.

6. The system for realizing high temperature field of materials based on laser-assisted heating according to claim 2, characterized in that: The high temperature furnace cooling water circulation (3) comprises: an industrial chiller connected to the high temperature furnace through a pipeline.

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