A device for toughening silicon nitride blank fibers

Abstract

The present invention discloses a device for toughening silicon nitride blank fiber, which is characterized by comprising a frame body, a fixing hook, a supporting body, a forming die with holes, a pressing plate die with holes, a hydraulic generator, a layered hook, a front supporting plate, and a rear supporting plate. The device penetrates the fiber bundle through the forming die with holes, and then places the fiber bundle in a fixed manner on both sides. The layered hook is used on the top to keep the top fiber bundle in a fully parallel state, ensuring that the pressing plate die with holes moves up and down without pulling the fiber bundle.

Description

Technical Field

[0001] The invention relates to the technical field of ceramic material production equipment, and in particular to a device for toughening silicon nitride blank fibers. Background Art

[0002] Silicon nitride ceramics have unique physical and chemical properties that make them an excellent choice for high-temperature structural materials, tool ceramic materials, wear-resistant materials, and corrosion-resistant materials. However, silicon nitride ceramics are polycrystalline sintered bodies composed of ionic or covalently bonded grains. The directionality of this chemical bond is extremely strong, resulting in low grain dislocation density and few slip systems, which makes the energy of crack growth small. In the fracture process, there is almost no other mechanism to dissipate energy except for increasing the new fracture surface energy, which leads to the shortcomings of silicon nitride ceramics such as insufficient toughness.

[0003] The existing method for preparing silicon nitride components is to mold silicon nitride powder and then sinter it. The silicon nitride ceramics produced by this technology have high strength but lack toughness. The present invention breaks through the above process limitations and adds fiber toughening technology. While maintaining the original characteristics of silicon nitride components, it overcomes the problem of insufficient toughness.

[0004] The significance of fiber toughening of silicon nitride blanks is to improve the fracture toughness of materials and enhance the crack resistance of components. By introducing fiber bundles into silicon nitride blanks, the mechanical properties of component materials can be effectively improved, making them have better fracture resistance and higher strength when subjected to external loads. The addition of fibers helps to disperse stress concentration and reduce the crack propagation rate, thereby extending the service life of components and improving their reliability in harsh environments such as high temperature and high pressure. Summary of the invention

[0005] The object of the present invention is to provide a device for toughening silicon nitride blank fibers. Under the action of the device, uniform fiber bundles are placed in the silicon nitride blank in the x, y and z directions. A layered fixing device is used on the top of the device, which is conducive to clearly seeing the position when fixing the fiber bundle and facilitating operation. It is also conducive to the upper and lower operation of the perforated pressure plate mold (5) without damaging the fibers.

[0006] A device for toughening silicon nitride green body fibers, characterized by comprising a frame body (1), a fixing hook (2), a support body (3), a forming die with holes (4), a pressing plate die with holes (5), a hydraulic generator (6), a layered hook (7), a front support plate (11), and a rear support plate (12).

[0007] Furthermore, the frame body (1) is a rectangular structure.

[0008] Furthermore, the support bodies (3) are provided on the left and right sides, respectively, and are used to support two sides of the hole-carrying forming mold (4), and the support bodies (3) are placed inside the frame body (1).

[0009] Furthermore, the frame body (1) has a fixing hook (2) on the left side, the frame body (1) has a fixing hook (2) on the right side, the frame body (1) has a fixing hook (2) on the lower side, the front support plate (11) has a fixing hook (2), and the rear support plate (12) has a fixing hook (2).

[0010] Furthermore, the outer surface of the porous forming mold (4) is a rectangular parallelepiped, the porous forming mold (4) has a porous pressure plate mold (5), the cavity portion of the porous forming mold (4) has a group of circular small holes of the same size, the porous forming mold (4) has a group of circular small holes, and the sizes of the circular small holes are all the same; a single small hole in the group of circular small holes is on the same straight line as the small hole on its corresponding surface.

[0011] Furthermore, hydraulic generators (6) are connected to both sides of the perforated pressure plate mold (5), and the hydraulic generators (6) are connected to the top of the frame body (1).

[0012] Furthermore, the hierarchical hook (7) is composed of n single hooks, n is a positive integer, the single hooks are in a row and column lattice structure, the single hooks are L-shaped, the hook directions of the single hooks all point to the same direction A, and the length of the L-shaped single hook "|" increases row by row or column by column along direction B, and direction B is the opposite direction of direction A.

[0013] Preferably, the single hook has a width, which is equal to the hole spacing on the corresponding perforated pressure plate mold (5).

[0014] Preferably, the two fiber bundles on both sides of a single hook can penetrate two adjacent holes on the perforated pressing plate mold (5) in a straight line.

[0015] Preferably, the single hook has a color, and the single hooks of the L-shaped single hook “|” with the same length adopt the same color; and the single hooks of the L-shaped single hook “|” with different lengths adopt different colors. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation of the present invention or the technical solution in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation or the prior art description:

[0017] Figure 1 A structural diagram of a device for toughening silicon nitride green body fibers;

[0018] Figure 2 is a side view of a device for toughening silicon nitride green body fibers;

[0019] Figure 3 The main view for the hierarchical hook;

[0020] Figure 4 This is a bottom view of the layer hook. DETAILED DESCRIPTION

[0021] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0022] For ease of understanding, the blank component of this embodiment is a cube with dimensions of 50 mm×50 mm×50 mm.

[0023] Prepare 2 sets of identical rectangular forming molds, take one set of forming mold A, and punch holes in the effective parts of the 5 faces of the main body and 1 face of the pressing plate. The holes are circular holes with a hole diameter of 1mm and a hole density of 2mm×2mm. The effective part refers to the position of each face corresponding to the shape of the cavity part in the mold component. The punching dot matrix of each face of forming mold A is 23*23, and the cavity section is a square. 1mm must be reserved at the four corners of the square, and the center of the circle must start from 3mm. The holes on the parallel faces can be penetrated by a straight line.

[0024] Silicon nitride powder is added into the molding mold A to keep the silicon nitride powder in a loose state.

[0025] Prepare a long needle, which must remain straight. The straightness of the long needle needs to be tested every 20 times it is used. The end of the long needle is flat, with a round hole in the flat part, and fiber filaments are tied to the round hole, which hold the fiber bundle. The length of the long needle is greater than the length of the mold, and it can directly penetrate the mold. The long needle is inserted into the round holes of the molding mold A in turn. The long needle is guided by a fixed guide on one side, and the long needle penetrates the corresponding round holes through the linearity of the long needle. After the long needle penetrates the molding mold A, it brings out the fiber bundle, which is composed of 4 strands of 3k carbon fiber bundles and does not need to be twisted. The carbon fiber bundle is fixed at a fixed point on one side of the bringing-out surface, and the long needle is inserted into the second round hole, penetrates the molding mold A, and brings out the carbon fiber bundle on the other side, and is fixed at a fixed point on the other side. During this period, the carbon fiber is kept in a taut state. Under reciprocating work, the carbon fiber bundle fully penetrates all the round holes of the molding mold A in the x direction. The same method is used to penetrate the round holes in the y and z directions.

[0026] The z-direction pressing plate mold A is a movable pressing plate, and the z-direction carbon fiber is preferentially fixed on the lower hook. The number of layer hooks corresponds to the number of small round holes in the pressing plate mold A. The z-direction carbon fiber is connected to the long needle, and penetrates the molding mold A from the lower right to the upper side. After penetration, it is fixed on the longest layer hook. The carbon fiber bundle is folded 90° twice and then penetrates downward the corresponding small hole just adjacent to it until it penetrates the molding mold A, passes out from the bottom, and is fixed on the lower hook. Repeat the above steps until the longest layer hook is fully wrapped with carbon fiber bundles, continue to repeat the above steps until the second length layer hook is fully wrapped with carbon fiber bundles, continue to repeat the above steps until all layer hooks are fully wrapped with carbon fiber bundles, and finally all carbon fiber bundles above the molding mold A are formed in a parallel state to ensure that the pressing plate mold A remains perpendicular to the carbon fiber bundles and does not damage the carbon fiber bundles during its activity.

[0027] The pressing plate mold A slowly presses the silicon nitride powder. Each time it is pressed, a little silicon nitride powder is added to the surface. This step is repeated 20 times. After pressing out a cube shape, the exposed carbon fiber bundle is cut off, the mold is opened to take out the cube silicon nitride blank, and then the exposed carbon fiber bundle is cut off.

[0028] The green body is placed into a forming mold B and hydraulically formed again to obtain a final toughened green body.

Claims

1. A device for toughening silicon nitride green body fibers, characterized in that: The invention comprises a frame body (1), a fixing hook (2), a support body (3), a forming die with a hole (4), a pressing plate die with a hole (5), a hydraulic generator (6), a layer hook (7), a front supporting plate (11), and a rear supporting plate (12); the supporting bodies (3) are one on each side and are used to support the two sides of the forming die with a hole (4), and the supporting bodies (3) are placed in the frame body (1); the left side of the frame body (1) has a fixing hook (2), the right side of the frame body has a fixing hook (2), the lower side of the frame body (1) has a fixing hook (2), the front supporting plate (11) has a fixing hook (2), and the rear supporting plate (12) has a fixing hook (2); the outer surface of the forming die with a hole (4) is a rectangular parallelepiped, The hole forming mold (4) has a hole pressing plate mold (5), the cavity portion of the hole forming mold (4) has a circular small hole group of the same size, the hole forming mold (4) has a circular small hole group, and the circular small holes are all the same size; the individual small holes of the circular small hole group are on the same straight line as the small holes on the corresponding surface; the hole pressing plate mold (5) is connected to a hydraulic generator (6) on both sides, and the hydraulic generator (6) is connected to the top of the frame body (1); the layered hook (7) is composed of n single hooks, n is a positive integer, the single hooks are in a row and column lattice structure, the single hooks are L-shaped, the hook directions of the single hooks all point to the same direction A, and the length of the L-shaped single hook "|" increases row by row or column by column along direction B, and direction B is the opposite direction of direction A.

2. The device for toughening silicon nitride green body fibers according to claim 1, characterized in that: The single hook has a width, which is equal to the hole spacing on the corresponding hole-carrying pressure plate mold (5).

3. The device for toughening silicon nitride green body fibers according to claim 1, characterized in that: The two fiber bundles on both sides of the single hook can linearly penetrate two adjacent holes on the perforated pressure plate mold (5).

4. The device for toughening silicon nitride green body fibers according to claim 3, characterized in that: The single hooks have colors, and the single hooks of the L-shaped single hook "|" with the same length adopt the same color; the single hooks of the L-shaped single hook "|" with different lengths adopt different colors.

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