Preparation method and application of a shape memory locking / releasing mechanism

Abstract

A preparation method and application of a shape memory locking / releasing mechanism, belonging to the technical field of shape memory composite material preparation, comprising the following steps: Step 1, mixing liquid metal and alcohol and subjecting the mixture to ultrasonic treatment to obtain an alcohol-liquid metal suspension; Step 2, coating the alcohol-liquid metal suspension on the left and right two regions of carbon cloth, and volatilizing the alcohol to obtain carbon cloth-liquid metal; Step 3, leading out electrodes on both sides of each liquid metal region; Step 4, stacking the carbon cloth without coating liquid metal and the carbon cloth coated with liquid metal together, pouring in a resin that can achieve two-stage curing, and after the resin completes the first-stage curing, completing the second-stage curing of one of the liquid metal regions; Step 5, heating the resin that has completed the second-stage curing again, bending it to lock the structural member I; bending the other liquid metal region to fit the structural member II, and completing the second-stage curing of this region to form a shape memory locking / releasing mechanism.

Description

Technical Field

[0001] The present invention belongs to the technical field of the preparation of shape memory composite materials, and particularly relates to a preparation method and application of a shape memory locking / releasing mechanism with high bearing capacity and self-heating two-stage curing. Background Art

[0002] When a space vehicle or a manned satellite is performing tasks in orbit, two spacecrafts need to be docked. The connection part needs to have a high-strength structure to achieve "locking", and after the task is completed, the connection also needs to be disconnected for "releasing".

[0003] The locking and releasing device is an important institutional condition for enabling the spacecraft system to perform services such as on-orbit assembly, expansion, and upgrade. These devices are mostly complex mechanical structures made of metal. Traditional ones include conical rod type, claw type and other mechanisms, but they are relatively complex, have high precision requirements, and basically do not have the ability of separation and release. Other pressing and releasing mechanisms are pyrotechnic devices, which use gunpowder combustion or explosion to achieve the release of components. In terms of function realization, the explosion will have a certain impact on the overall structure and the entire spacecraft, causing damage to the delicate electronic equipment on the spacecraft, and there are potential safety hazards. Moreover, pyrotechnic devices have relatively high requirements for storage and transportation. Summary of the Invention

[0004] To solve the problems in the background art, the present invention provides a preparation method and application of a shape memory locking / releasing mechanism.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A preparation method of a shape memory locking / releasing mechanism, comprising the following steps:

[0007] Step 1: Under an inert atmosphere or in a vacuum environment, mix liquid metal and alcohol and perform ultrasonic treatment to obtain an alcohol-liquid metal suspension;

[0008] Step 2: Uniformly coat the alcohol-liquid metal suspension on the left and right two regions of the carbon cloth, and the alcohol volatilizes to obtain carbon cloth-liquid metal;

[0009] Step 3: Lead out electrodes on both sides of each liquid metal region;

[0010] Step 4: Stack the carbon cloth without liquid metal coating and the carbon cloth with liquid metal coating together to form a structural unit, stack multiple structural units together to obtain multi-layer carbon cloth, place the multi-layer carbon cloth in a mold, pour in a resin that can achieve two-stage curing, and after the resin completes the first-stage curing, connect the electrodes on both sides of one of the liquid metal regions to a power supply for heating to complete the second-stage curing of the resin in this region;

[0011] Step 5: Apply power again to the resin that has completed the second-stage curing, heat it up to a temperature above the Tg of the resin, bend it to lock the structural member I to be released; bend the other liquid metal area to fit the structural member II, and connect the electrodes on both sides to the power supply to heat and complete the second-stage curing of this area, forming a shape memory locking / releasing mechanism.

[0012] Further, in Step 1, the liquid metal includes one or a combination of two of Component A and Component B. Component A includes one or a combination of two of gallium and indium; Component B includes one or a combination of one or more of liquid metal alloys composed of two or more metal elements among gallium, indium, zinc, tin, bismuth, and silver.

[0013] Further, in Step 1, the liquid metal is placed in a mixed acid for cleaning before use. The mixed acid includes an organic acid solution and an inorganic acid solution. The volume ratio of the inorganic acid solution to the organic acid solution is 1:(0.25 - 4). The mass fraction of the organic acid solution is 80% - 100%, and the concentration of the inorganic acid solution is 0.5 - 5 mol / L.

[0014] Further, the organic acid includes one or a combination of formic acid, acetic acid, and acrylic acid, and the inorganic acid includes one or a combination of sulfuric acid, hydrochloric acid, and nitric acid.

[0015] Further, in Step 1, the alcohol includes a mixture of ethanol and thiol. The mass ratio of ethanol to thiol is 1 - 3:10. The thiol includes one or a combination of ethyl mercaptan, 1,3-propanedithiol, ethylene dithiol, and 1-propanethiol.

[0016] Further, in Step 2, the carbon cloth is soaked in a nitric acid solution with a mass fraction of 60 - 90%, an acidic potassium permanganate solution with a mass fraction of 5 - 20%, an acidic potassium dichromate solution with a mass fraction of 5 - 20%, or hydrogen peroxide with a mass fraction of 10 - 20% before use. The temperature is set at 50 - 120°C, and the soaking duration is 10 - 40 min. The treated carbon cloth is washed with acetone in a fume hood and used after the acetone has completely evaporated.

[0017] Further, in Step 4, in each structural unit, the number of layers of the carbon cloth without liquid metal coating is 1 - 3 layers; the number of layers of the multi-layer carbon cloth is 5 - 30 layers.

[0018] Further, in Step 4, the resin capable of two-stage curing includes Component C, Component D, and Component E. The mass ratios of Component C and Component D are 70%-80% and 20%-30% respectively, and the mass of Component E is 0.1%-1% of the mass of Component C; Component C includes one or a combination of more of hydroxyethyl acrylate, polyurethane acrylate, tripropylene glycol diacrylate, 1,6-hexanediol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, 2-hydroxypropyl methacrylate; Component D includes one or a combination of more of ethylene dithiol, 1,3-propanedithiol, 1,5-pentanedithiol, trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptopropionate); Component E includes one of benzoyl peroxide, azobisisobutyronitrile, cumene hydroperoxide, tert-butyl hydroperoxide, di-tert-butyl peroxide.

[0019] An application of the shape memory locking / releasing mechanism described above includes the following steps:

[0020] S1: After the resin completes the first-stage curing, power is supplied to the electrodes on both sides of one of the liquid metal regions to heat and complete the second-stage curing of the resin in this region, while the other liquid metal region remains in the soft state after the first-stage curing.

[0021] S2: Power is supplied to the liquid metal region that has completed the second-stage curing again to raise the temperature above the Tg of the resin, and it is bent to fit Structural Member I.

[0022] S3: Bend the other liquid metal region to fit Structural Member II, and power is supplied to the electrodes on both sides of this liquid metal region to complete the second-stage curing of the resin in this region for locking Structural Member I and Structural Member II.

[0023] S4: Power is supplied to the electrodes on both sides of the liquid metal region that fits Structural Member I again. When the temperature rises above the Tg, this end returns to the straight state to complete the release of Structural Member I.

[0024] Further, in S3, a support sheet is pasted on the back of the carbon cloth of the other liquid metal region.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] (1) This structure is a multi-layer carbon fiber composite material, which has the characteristics of small mass and high strength. It has a comparable structural strength to metal, and at the same time is much lighter in mass than the metal structure.

[0027] (2) Compared with other complex, multi-component, and high-precision mechanical structures, this structure has a low manufacturing cost, simple assembly, and low precision requirements.

[0028] (3) Compared with other shape memory materials, this structure can self-heat, without customization and without using a heating film, reducing the impact of the heating film on the deformation ability.

[0029] (4) This structure can not only achieve the "locking" of the docking of two spacecraft, but also multiple identical structures can be used simultaneously as the "load connection" structure for bridging. Description of the Drawings

[0030] Figure 1 is a schematic diagram of the carbon cloth-liquid metal structure;

[0031] Figure 2 is a schematic diagram of the multi-layer carbon cloth structure located in the mold;

[0032] Figure 3 is a cross-sectional schematic diagram of the shape memory locking / releasing mechanism for locking Structure A;

[0033] Figure 4 is a cross-sectional schematic diagram of the shape memory locking / releasing mechanism for locking Structure A and Structure B;

[0034] Figure 5 is a cross-sectional schematic diagram of the shape memory locking / releasing mechanism for releasing Structure A. Detailed Embodiments

[0035] Next, the technical solutions in the present invention will be clearly and completely described in conjunction with the drawings and embodiments. Obviously, the described embodiments are only a part of the embodiments of the invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention. The words indicating directions such as "left" and "right" in the present invention are only for the convenience of clear description and do not represent specific limitations on the present invention.

[0036] The shape memory composite material made of shape memory polymer and carbon fiber reinforcement (carbon cloth) retains the shape memory while having a certain structural strength and can return to the initial shape under certain stimuli. Two-stage curing means that the system contains a matrix resin and two curing agents, namely a room temperature type curing agent and a latent type curing agent. By controlling the reaction conditions, two independent curing reactions can be achieved. The first stage is the reaction of the resin and the room temperature type curing agent. After the curing reaction, the system basically has a certain shape and is relatively soft in texture. The second stage curing is under another condition, where the matrix resin and the latent type curing agent react, and the whole material becomes hard after curing, having a certain strength and stiffness.

[0037] The present invention provides a shape memory locking / releasing mechanism that can achieve the docking of two spacecrafts. By using carbon fiber-reinforced shape memory polymers, the "locking" of the structure is realized through two-stage curing, and the "releasing" of the structure is realized by the recovery ability of the shape memory composite material. The "locking / releasing" mechanism that combines function and strength can achieve the docking locking or releasing of two spacecrafts with almost no impact, and is pollution-free, lightweight and high-strength.

[0038] The experimental production process is as follows:

[0039] (1) Prepare carbon fiber cloth, cut several pieces of carbon cloth with a size of (5-15) cm * (20-40) cm, immerse the cut carbon cloth in a nitric acid solution with a mass fraction of 60-90%, an acidic potassium permanganate solution with a mass fraction of 5-20%, an acidic potassium dichromate solution with a mass fraction of 5-20%, or hydrogen peroxide with a mass fraction of 10-20%. Set the temperature at 50-120 °C and the soaking time at 10-40 min. Wash the treated carbon fiber cloth with acetone in a fume hood and wait for the acetone to completely volatilize before use.

[0040] (2) Take one or more inorganic acid solutions from sulfuric acid solution with a concentration of 0.5-5 mol / L, hydrochloric acid solution with a concentration of 0.5-5 mol / L, and nitric acid solution with a concentration of 0.5-5 mol / L, and take one or more small molecule organic acids from formic acid, acetic acid, and acrylic acid. Mix the inorganic acid solution and the organic acid according to a volume ratio of 1: (0.25-4). Take 40-80 ml of the mixed acid solution and place it in a beaker for standby.

[0041] (3) Prepare 10-40 g of liquid metal. The liquid metal includes one or a combination of two of component A and component B. Component A includes one or a combination of two of gallium and indium; Component B includes one or a combination of one or more of liquid metal alloys composed of two or more metal elements among gallium, indium, zinc, tin, bismuth, and silver. Heat and melt the liquid metal or liquid metal alloy. Put the melted liquid metal into the beaker of the above mixed acid solution, shake it, and stir for 1-5 min.

[0042] (4) Under an inert atmosphere or in a vacuum environment, mix one or more thiols with a molecular weight less than 200, such as ethanethiol, ethylene dithiol, 1-propanethiol, or 1,3-propanedithiol, with ethanol in a mass ratio of (1-3):10. Take 30-60 ml of the mixed alcohol solution, shake it, stir it evenly, pour it into a bottle with a lid, use a syringe or a straw to transfer the liquid metal in the mixed acid solution to the bottle containing thiol-ethanol, tighten the bottle cap, and stick a sealing strip or a sealing tape.

[0043] (5) Place the vial containing the alcohol-liquid metal in an ultrasonic disperser and perform ultrasonic treatment for 5 - 30 minutes at a temperature set to 80 - 200 °C (not lower than the melting point of the liquid metal) to obtain an alcohol-liquid metal suspension.

[0044] (6) Prepare a resin that can be cured in two stages. The resin that can be cured in two stages includes component C, component D, and component E. The mass ratios of component C and component D are 70% - 80% and 20% - 30% respectively, and the mass of component E is 0.1% - 1% of the mass of component C; component C is a matrix resin that can be cured in two stages, including one or a combination of more of hydroxyethyl acrylate, polyurethane acrylate, tripropylene glycol diacrylate, 1,6 - hexanediol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, 2 - hydroxypropyl methacrylate; component D is a room-temperature curing agent, including one or a combination of more of ethylene dithiol, 1,3 - propanedithiol, 1,5 - pentanedithiol, trimethylolpropane tris(3 - mercaptopropionate), pentaerythritol tetrakis(3 - mercaptopropionate); component E is a latent curing agent used to initiate the curing of carbon-carbon double bonds in the second stage, including one of benzoyl peroxide, azobisisobutyronitrile, cumene hydroperoxide, tert-butyl hydroperoxide, di-tert-butyl peroxide. When preparing the resin that can be cured in two stages, mix component E and component D evenly, and then mix and stir the mixture with component C, and perform ultrasonic treatment to remove air bubbles in the system.

[0045] (7) Place the alcohol-liquid metal suspension, the carbon cloth cleaned with acetone, and the electrodes in a glove box. Evenly drip or spray the alcohol-liquid metal suspension on the left and right areas of the carbon cloth. By changing the amount of the dripped or sprayed suspension, the resistance can be adjusted. After the alcohol has evaporated, lead out electrodes on both sides of each liquid metal area, see Figure 1 , and the electrodes are connected to the carbon cloth through the cured liquid metal.

[0046] (8) Assemble the mold. Prepare 2 glass plates slightly larger than the carbon cloth, stick release cloth, and place a 5 - 15 mm thick "U" - shaped frame flat on the glass plates, see Figure 2 . Alternately stack 1 - 3 layers of non-coated liquid metal carbon fiber cloth and 1 layer of liquid metal-coated carbon fiber cloth to form multiple layers of carbon cloth. The total number of carbon fiber cloths used is 5 - 30 layers. Place the multiple layers of carbon cloth in the middle of the "U" - shaped frame, lead the wires out along the carbon fiber cloth from the side, cover the glass plates, and stick sealant on the side.

[0047] (9) Slowly pour the prepared resin that can be cured in two stages into the mold. After the first-stage curing of the resin, remove the glass plate for demolding. Subsequently, by connecting the power supply and heating up, the left or right side can be hardened through the second-stage curing. Since the area without liquid metal coating in the middle is relatively small, the middle part can be cured when the second-stage curing is carried out on one side, while the other side remains in the soft state after the first-stage curing.

[0048] (10) Re-power and heat up the side (left side) that has completed the second-stage curing to a temperature above the Tg of the resin. Use a specific bending tool to bend it into a hook shape. The hook can be assembled with the black load-bearing structural member I on the ground. The bending diameter of the hook is 3 - 8 cm, and it just needs to fit the load-bearing structural member I. Paste a support sheet on the back of the soft material on the other side (right side) that has not completed the second-stage curing. The support sheet can be a thin copper sheet, or a single-layer or multi-layer fiber-reinforced composite material sheet, etc., as long as it has a certain toughness. The right gray semi-circle and the middle gray load-bearing part are structural member II, which is a certain structure of another spacecraft that needs to be docked, such as Figure 3 shown.

[0049] (11) In the space environment, the No. I spacecraft with structural member I and that has completed the ground assembly with the left hook can dock the soft material on the other side that has not completed the second-stage curing into the No. II spacecraft containing structural member II. Due to the structural state of its soft material, it can smoothly enter and be bent into a hook shape. At this time, power on and heat to make the right hook undergo the second-stage curing. After the curing is completed, since multi-layer carbon fiber composite material is used, the strength is very high, and a "locking state" with high load-bearing capacity can be achieved, as Figure 4 shown.

[0050] (12) To achieve "release", power on and heat the shape memory locking / release mechanism on the side where structural member I is located. When the temperature rises above the Tg, the hook locking structural member I becomes soft and can return to a nearly straight state relying on shape memory, thus realizing the release of structural member I, that is, completing the "release" of the No. II spacecraft from the No. I spacecraft, as Figure 5 shown.

[0051] Example 1

[0052] A preparation method of a shape memory locking / release mechanism: The experimental production process is as follows:

[0053] (1) Prepare carbon fiber cloth, cut several pieces of carbon cloth into a size of 5 cm * 20 cm. Immerse the cut carbon cloth in hydrogen peroxide with a mass fraction of 15%, set the temperature at 50 °C, and the soaking time at 20 min. Wash the treated carbon fiber cloth with acetone in a fume hood and wait for the acetone to completely volatilize before use.

[0054] (2) Take a 0.5 mol / L sulfuric acid solution and acrylic acid. Mix the organic acid and the inorganic acid in a volume ratio of 4:1. Take 50 ml of the mixed acid solution and place it in a beaker for later use.

[0055] (3) Prepare 10 g of liquid metal gallium. Put the melted liquid metal into the beaker with the above mixed acid solution, shake it, and stir for 2 min.

[0056] (4) Under an inert atmosphere or in a vacuum environment, mix ethanedithiol and ethanol in a mass ratio of 1:5. Take 30 ml of the mixed alcohol solution, shake it, and after stirring evenly, pour it into a bottle with a lid. Use a syringe or a pipette to transfer the liquid metal in the mixed acid solution to the bottle containing thiol-ethanol. Tighten the bottle cap and paste a sealing strip or sealing tape.

[0057] (5) Place the vial containing alcohol-liquid metal in an ultrasonic disperser for ultrasonic treatment for 10 min at a temperature set to 80 °C to obtain an alcohol-liquid metal suspension.

[0058] (6) Prepare a resin that can be cured in two stages. Component C: Take 70 g of polyurethane acrylate, Component D: Take 30 g of trimethylolpropane tris(3-mercaptopropionate), Component E: Take 0.5 g of azobisisobutyronitrile. Among them, when preparing the resin that can be cured in two stages, mix Component E and Component D evenly, and then mix and stir the mixture with Component C. Use ultrasonic treatment to remove the air bubbles in the system.

[0059] (7) Put the alcohol-liquid metal suspension, the carbon cloth washed with acetone, and the electrodes into the glove box. Evenly drip or spray the alcohol-liquid metal suspension on the left and right areas of the carbon cloth. By changing the amount of the dripped or sprayed suspension, the regulation of the resistance value can be achieved. After waiting for the alcohol to volatilize, lead out electrodes on both sides of each liquid metal area, see Figure 1 , and the electrodes are connected to the carbon cloth through the solidified liquid metal.

[0060] (8) Assemble the mold. Prepare 2 glass plates slightly larger than the carbon cloth, paste a release cloth, and prepare a 5-mm-thick "U"-shaped frame and place it flat on the glass plate, see Figure 2 . Alternately lay every 1 layer of carbon fiber cloth without liquid metal coating and 1 layer of carbon fiber cloth with liquid metal coating together to form multiple layers of carbon cloth. The total number of carbon fiber cloths used is 10 layers. Place the multiple layers of carbon cloth in the middle of the "U"-shaped frame, lead the wire out along the carbon fiber cloth from the side, cover the glass plate, and paste a sealant on the side.

[0061] (9) Slowly pour the prepared resin that can be cured in two stages into the mold. After the first-stage curing of the resin, remove the glass plate for demolding. Subsequently, by connecting the power supply and heating up, the left or right side can be hardened through the second-stage curing. Since the range without liquid metal coating in the middle is small, the middle part can be cured when the second-stage curing is carried out on one side, while the other side remains in the soft state after the first-stage curing.

[0062] (10) Supply power again to the cured side (left side) in the second stage and heat it up to above the Tg of the resin. Use a specific bending tool to bend it into a hook shape. The hook can be assembled with the black load-bearing structural member Ⅰ on the ground. The bending diameter of the hook is 3 cm, which can fit the load-bearing structural member Ⅰ. Stick a support sheet on the back of the soft material on the other side (right side) that has not completed the second-stage curing. The support sheet can be a thin copper sheet, or a single-layer or multi-layer fiber-reinforced composite material sheet, etc., as long as it has a certain toughness. The right gray semi-circle and the middle gray load-bearing part are structural member Ⅱ, which is a certain structure of another spacecraft that needs to be docked, such as Figure 3 shown.

[0063] (11) In the space environment, the No. Ⅰ spacecraft with structural member Ⅰ and completed ground assembly with the left hook can dock the soft material on the other side that has not completed the second-stage curing into the No. Ⅱ spacecraft containing structural member Ⅱ. Due to the structural state of its soft material, it can smoothly enter and be bent into a hook shape. At this time, power is supplied for heating to carry out the second-stage curing of the right hook. After the curing is completed, since multi-layer carbon fiber composite materials are used, the strength is very high, and a "locking state" with high bearing capacity can be achieved, as Figure 4 shown.

[0064] (12) To achieve "release", supply power and heat the shape memory locking / release mechanism on the side where structural member Ⅰ is located. When the temperature rises above Tg, the hook locking structural member Ⅰ becomes soft and can return to a nearly straight state by relying on shape memory, thus realizing the release of structural member Ⅰ, that is, completing the "release" of the No. Ⅱ spacecraft from the No. Ⅰ spacecraft, as Figure 5 shown.

[0065] In addition, it should be understood that although this specification is described according to the embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A preparation method of a shape memory locking / releasing mechanism, characterized in that, It includes the following steps: Step 1: Under an inert atmosphere or in a vacuum environment, mix liquid metal with alcohol and perform ultrasonic treatment to obtain an alcohol-liquid metal suspension; Step 2: Uniformly coat the alcohol-liquid metal suspension on the left and right regions of the carbon cloth, and let the alcohol volatilize to obtain carbon cloth-liquid metal; Step 3: Lead out electrodes on both sides of each liquid metal region; Step 4: Stack the carbon cloth without coated liquid metal and the carbon cloth with coated liquid metal together to form a structural unit. Stack multiple structural units together to obtain multi-layer carbon cloth. Place the multi-layer carbon cloth in a mold, pour in a resin that can achieve two-stage curing. After the resin completes the first-stage curing, connect the electrodes on both sides of one of the liquid metal regions to a power supply and heat to complete the second-stage curing of the resin in this region; Step 5: Supply power to the resin that has completed the second-stage curing again to raise the temperature above the Tg of the resin, bend it to lock the structural part Ⅰ to be released; Bend the other liquid metal region to fit the structural part Ⅱ, and connect the electrodes on both sides of it to a power supply and heat to complete the second-stage curing of this region to form a shape memory locking / releasing mechanism.

2. The preparation method of a shape memory locking / releasing mechanism according to claim 1, wherein: In Step 1, the liquid metal includes one or a combination of two of Component A and Component B. Component A includes one or a combination of two of gallium and indium; Component B includes one or a combination of one or more of liquid metal alloys composed of two or more metal elements among gallium, indium, zinc, tin, bismuth, and silver.

3. The preparation method of a shape memory locking / releasing mechanism according to claim 1, characterized in that: In Step 1, the liquid metal is placed in a mixed acid for cleaning before use. The mixed acid includes an organic acid solution and an inorganic acid solution. The volume ratio of the inorganic acid solution to the organic acid solution is 1:(0.25 - 4). The mass fraction of the organic acid solution is 80% - 100%, and the concentration of the inorganic acid solution is 0.5 - 5 mol / L.

4. The preparation method of a shape memory locking / releasing mechanism according to claim 3, characterized in that: The organic acid includes one or a combination of formic acid, acetic acid, and acrylic acid. The inorganic acid includes one or a combination of sulfuric acid, hydrochloric acid, and nitric acid.

5. The preparation method of a shape memory locking / releasing mechanism according to claim 1, characterized in that: In Step 1, the alcohol includes a mixture of ethanol and thiol. The mass ratio of ethanol to thiol is 1 - 3:

10. The thiol includes one or a combination of ethyl mercaptan, 1,3-propanedithiol, ethylene dithiol, and 1-propanethiol.

6. The preparation method of a shape memory locking / releasing mechanism according to claim 1, characterized in that: In Step 2, the carbon cloth is soaked in a nitric acid solution with a mass fraction of 60 - 90%, an acidic potassium permanganate solution with a mass fraction of 5 - 20%, an acidic potassium dichromate solution with a mass fraction of 5 - 20%, or hydrogen peroxide with a mass fraction of 10 - 20% before use. The temperature is set at 50 - 120 °C, and the soaking time is 10 - 40 min. The treated carbon cloth is washed with acetone in a fume hood and used after the acetone has completely volatilized.

7. The preparation method of a shape memory locking / releasing mechanism according to claim 1, characterized in that: In Step 4, in each structural unit, the number of layers of the carbon cloth without coated liquid metal is 1 - 3 layers; the number of layers of the multi-layer carbon cloth is 5 - 30 layers.

8. A preparation method of a shape memory locking / releasing mechanism according to claim 1, characterized in that: In Step 4, the resin capable of achieving two-stage curing includes Component C, Component D, and Component E. The mass ratios of Component C and Component D are 70%-80% and 20%-30% respectively, and the mass of Component E is 0.1%-1% of the mass of Component C. Component C includes one or a combination of more than one of hydroxyethyl acrylate, polyurethane acrylate, tripropylene glycol diacrylate, 1,6-hexanediol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, 2-hydroxypropyl methacrylate; Component D includes one or a combination of more than one of ethylene dithiol, 1,3-propanedithiol, 1,5-pentanedithiol, trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptopropionate); Component E includes one of benzoyl peroxide, azobisisobutyronitrile, cumene hydroperoxide, tert-butyl hydroperoxide, di-tert-butyl peroxide.

9. Use of a shape memory locking / releasing mechanism prepared by the method according to any one of claims 1-8, characterized in that The method includes the following steps: S1: After the resin completes the first-stage curing, power is supplied to the electrodes on both sides of one of the liquid metal regions to heat and complete the second-stage curing of the resin in this region, while the other liquid metal region remains in the soft state after the first-stage curing. S2: Power is supplied again to the liquid metal region that has completed the second-stage curing to raise the temperature above the Tg of the resin, so that it bends to fit Structural Member Ⅰ. S3: Bend the other liquid metal region to fit Structural Member Ⅱ, and power is supplied to the electrodes on both sides of this liquid metal region to complete the second-stage curing of the resin in this region, which is used to lock Structural Member Ⅰ and Structural Member Ⅱ. S4: Power is supplied again to the electrodes on both sides of the liquid metal region that fits Structural Member Ⅰ. When the temperature rises above the Tg, this end returns to the straight state to complete the release of Structural Member Ⅰ.

10. The application according to claim 9, wherein: In S3, a support sheet is pasted on the back of the carbon cloth of the other liquid metal region.

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