A combined curing method for multi-feature silicate parts

Abstract

The application discloses a combined solidification method for multi-feature silicate parts, which adopts pressure extrusion molding methods, including but not limited to pressing method, extrusion method and injection molding method, and is characterized by the following steps: applying heating and pressure pushing to a feed made of a silicate mixture to liquefy the feed and inject the feed into a mold cavity to obtain a multi-feature silicate white body; coating a high-temperature adhesive on a combined feature surface of the individual multi-feature silicate white body after debinding; and completing solidification of the white body through a heat treatment process to form an integrated multi-feature silicate part. The application has the following advantages and effects: the white body can be split into multiple parts for injection molding, and more features can be obtained through additional processing; and the structure features of the white body parts can still meet the original design after being combined through the high-temperature adhesive.

Description

Technical Field

[0001] This invention relates to the field of chemical processing, and in particular to a combined curing method for multi-feature silicate parts. Background Technology

[0002] Silicates are materials that exhibit large areas of transparency in their solid state. Since their discovery, they have been used to create transparent devices for human use, such as windows, wine bottles, water glasses, and plates. Silicate containers allow light to pass through, making it easy to observe differences between the inside and outside, allowing people to make judgments and take action. For example, when it's raining outdoors, a transparent glass window tells us to bring rain gear; inside a jar of seasoning powder, we can easily see whether it's used up and what kind of seasoning it contains.

[0003] The manufacturing of commonly used silicate multi-feature parts mostly employs high-temperature melting processes, which are extremely energy-intensive and require numerous high-temperature resistant containers for transfer and storage. The most troublesome aspect is the very high viscosity of molten silicate at high temperatures, making efficient casting methods like steel casting impossible. Instead, a process of repeatedly filling, melting, and refilling with broken glass or powder is necessary, resulting in very low forming efficiency for most silicate components. Furthermore, high-speed powder forming is generally limited by mold release mechanisms, preventing many structural features from being formed in a single process. However, if silicate blanks could be individually fabricated using methods similar to metal welding, and then assembled together for a rapid, large-scale hot forming process to obtain a large quantity of final transparent blanks, it would be much more convenient and efficient.

[0004] Therefore, overcoming the low manufacturing efficiency of multi-feature silicate parts is the focus of the combined curing method for multi-feature silicate parts proposed in this invention. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method for the combined curing of multi-feature silicate parts. This method involves obtaining multi-feature silicate blanks from a silicate mixture through an appropriate forming method, applying a high-temperature adhesive to the combined feature surfaces of the individual multi-feature silicate blanks after degreasing, bonding them together, and then subjecting them to a thermal process to complete the curing process and form an integrated multi-feature silicate part.

[0006] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a combined curing method for multi-feature silicate parts, characterized in that a pressure extrusion molding method is adopted, including but not limited to pressing, extrusion and injection molding, to heat and press the feed made of silicate mixture to liquefy it and inject it into the mold cavity to obtain a multi-feature silicate blank.

[0007] High-temperature adhesive is applied to the combined feature surfaces of individual multi-feature silicate blanks after degreasing;

[0008] The above-mentioned blank is cured by a thermal process to become an integrated multi-feature silicate part.

[0009] The present invention is further configured such that: the high-temperature adhesive comprises silicate powder, binder, and the weight ratio of silicate powder, binder and water is 1:(1-3):(1-3).

[0010] The present invention is further configured such that the adhesive is a water-soluble polymer material such as polyvinyl alcohol, polyethylene glycol, or polyacrylamide.

[0011] The present invention is further configured such that the silicate powder in the high-temperature adhesive has a particle size of less than 10 μm.

[0012] The present invention is further configured such that the adhesive is dissolved in hot water at 70-90℃ during the preparation of the high-temperature adhesive.

[0013] The present invention is further configured such that the coating method of the high-temperature adhesive includes, but is not limited to, hand brushing, dip plating, spraying, etc., and the coating thickness is between 0.01-0.2 mm.

[0014] The present invention is further configured such that: the feed is prepared from silicate powder and binder, wherein the particle size of the silicate powder is in the range of 0.5-0.6 μm, and the binder includes lubricant and activator, powder entrainer, skeleton agent and graft toughening agent, etc.

[0015] The present invention is further configured such that: the lubricant and activator is one or more of stearic acid, paraffin wax, microcrystalline wax, Fischer-Tropsch wax, polyethylene wax, ethylene bis-stearamide, and pentaerythritol stearate; the powder entrainer is copolyoxymethylene; and the skeleton agent is one or more of polyethylene and polypropylene.

[0016] The present invention is further configured such that the lubricant and activator also includes a toughening grafting agent, specifically one or more of ethylene-vinyl acetate copolymer and butadiene rubber.

[0017] The present invention is further configured such that the weight ratio of the lubricant and activator is 0.2-20%;

[0018] The powder entrainer accounts for 60-93% by weight;

[0019] The weight percentage of the skeleton agent is 3-25%;

[0020] The toughening grafting agent accounts for 0.5-10% by weight.

[0021] Because a product with a unique feature has uneven wall thickness and an undercut design, as well as narrow exit requirements, it is difficult to obtain this silicate product quickly and efficiently using traditional processes or even molding. Compared with the prior art, the advantages of this invention are: by using a mold to inject silicate blank parts into an upper body and a lower base, or even more parts, the combined features completely conform to the original design, but can be quickly produced using molding (without the undercut feature). Simultaneously, the blank obtained in this application can undergo further processing to obtain more features, giving the blank more combined features for subsequent thermoforming and curing. For example, secondary processing can be performed on the original silicate blank to obtain additional combined features such as grooves and protrusions, thereby satisfying other more flexible designs. The subsequent thermoforming process of sintering and curing the combined multi-feature silicate blank results in an integrated multi-feature silicate part with transparent blank characteristics. A sintering furnace with controllable temperature, time, pressure, atmosphere type, and flow rate is used to cure the multi-feature silicate combined part, obtaining the final transparent blank. Attached Figure Description

[0022] Figure 1 This is a manufacturing process diagram of the present invention. Detailed Implementation

[0023] The technical solutions described in this invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. Obviously, the embodiments described in this specification are only some feasible technical solutions of this invention. Other embodiments obtained by those skilled in the art based on the embodiments of this invention without any creative effort should be considered to fall within the scope of protection of this invention.

[0024] A method for combining and curing multi-feature silicate parts is characterized by employing a pressure extrusion molding method, including but not limited to pressing, extrusion, and injection molding. A feedstock made from a silicate mixture is heated and pressure-pressed to liquefy it and injected into a mold cavity. After cooling and solidification, the molded product is removed and referred to as a blank. At this point, the blank already possesses multiple features in multiple directions, such as combined features like mortise and tenon structures in woodworking, mating flanges, etc. In the embodiments of this application, the silicate blank part is assembled into an upper body and a lower base, or even more components. After obtaining the aforementioned components through mold injection, the target shape product is obtained through assembly, thereby achieving the goal of quickly manufacturing the target product using molding methods.

[0025] In addition, the blank parts can undergo further processing to obtain more features, thus giving the blank more combination features for use as a blank in subsequent thermal curing processes. This makes the design more flexible and reduces the difficulty of processing and manufacturing.

[0026] After completing the above steps, the blank of the multi-feature silicate part is first degreased. The purpose of degreasing is to remove the binder in the blank. The degreasing method of this application is suitable for different binder formulations and can be thermal degreasing, catalytic degreasing, solvent degreasing, and combined degreasing operation modes.

[0027] After completing the above steps, a high-temperature adhesive is applied to the combined feature surfaces of individual multi-feature silicate blanks after degreasing.

[0028] The above-mentioned blank is cured by a thermal process to become an integrated multi-feature silicate part.

[0029] The present invention is further configured to include a high-temperature adhesive preparation, wherein the high-temperature adhesive is composed of silicate powder, using particles with a particle size of less than 10 μm, and when the weight of silicate powder is 1 part, the adhesive is 1-3 parts and the water is 1-3 parts. The silicate powder, adhesive and water in the above proportion are dispersed evenly and ready for use.

[0030] The adhesive is a water-soluble polymer such as polyvinyl alcohol, polyethylene glycol, or polyacrylamide; the silicate powder in the high-temperature adhesive has a particle size of less than 10 μm; the high-temperature adhesive is prepared by dissolving the adhesive in hot water at 70-90℃, such as 80℃; the coating method of the high-temperature adhesive includes, but is not limited to, hand brushing, dip plating, and spraying, and the coating thickness is between 0.01-0.2 mm.

[0031] As shown in Table 1, several embodiments can be used to formulate high-temperature binders for multi-feature silicate blanks. In each embodiment, hot water is used to dissolve the binder and to ensure that the silicate powder is uniformly dispersed in the binder solution.

[0032] The combined multi-feature silicate blanks are subjected to sintering and curing followed by a thermal process to obtain an integrated multi-feature silicate part with transparent blank characteristics after curing. The curing operation of the multi-feature silicate composite part is carried out using a sintering furnace with controllable temperature, time, pressure, atmosphere type and flow rate to obtain the final transparent blank.

[0033] Table 1 Examples of high-temperature adhesive strip formulations

[0034]

[0035] The present invention is further configured such that: the feed is prepared from silicate powder and binder, wherein the particle size of the silicate powder is in the range of 0.5-0.6 μm, and the binder includes lubricant and activator, powder entrainer, skeleton agent and graft toughening agent, etc.

[0036] The preparation of feed includes the following steps:

[0037] Step 1: Preparation of silicate powder: Select silicate powder with a particle size of 0.5-60μm;

[0038] Step 2: Preparation of binder powder: This includes lubricant and activator, skeleton agent, and powder entrainer. After mixing the above raw materials, use a pulverizer to pulverize them so that the particle size reaches between 10-30μm.

[0039] Step 3, Preparation of feed precursor: Mix the silicate powder from Step 1 with the binder powder from Step 2 at a certain volume ratio;

[0040] Step 4, Mixing: Place the feed precursor from Step 3 into the mixing chamber and form the feed precursor into feed lumps;

[0041] Step 5: Granulation: Cool the feed clumps appropriately and extrude and cut them into small granules or powder;

[0042] Step 6: Catalytic degreasing: to obtain porous yellow blanks from white blanks.

[0043] In step one, the silicate powder used is commercially available conventional silicate powder. The powder shape should preferably be equiaxed, including spherical and irregular shapes. Specifically, the sources of silicate powder include, but are not limited to:

[0044] Various transparent and opaque silicate materials, as well as materials of different colors and with added inorganic powders;

[0045] Silicate sheet materials and their scraps;

[0046] Defective or scrapped products from the manufacturing process of conventional silicate products;

[0047] Recycled materials from commercial silicate products, etc.

[0048] The binder powder used in step two is also a commercially available conventional polymer material;

[0049] In step three, the ratio of silicate powder and binder powder is calculated, weighed, and mixed according to Archimedes' principle, and then put into a premixer for mixing to form a feed precursor.

[0050] Furthermore, in the components of the adhesive powder in step two, the lubricant and activator are specifically one or more of stearic acid, paraffin wax, microcrystalline wax, Fischer-Tropsch wax, polyethylene wax, ethylene bis-stearamide, and pentaerythritol stearate; the softening temperature range of the above lubricant and activator is between 50-120°C. In the technical solution of this application, its main function is to fill the pores and wet the surface of the silicate powder, thereby enabling it to bond with other adhesives.

[0051] Furthermore, the powder entrainer is copolymerized polyoxymethylene, i.e., polyoxymethylene plastic, with a softening temperature range of 160-170℃. In the technical solution of this application, its main function is to coat the powder and carry the powder along with it during the feeding and melting process.

[0052] Furthermore, the skeleton agent is one or more of polyethylene and polypropylene, with a softening temperature range of 140-160℃. Its main function is to support the powder-molded preform during the process of 25-600℃.

[0053] Furthermore, in the technical solution of this application, the lubricant and activator also includes a toughening grafting agent, specifically one or more of ethylene-vinyl acetate copolymer and butadiene rubber. Its main function is to assist in the mutual solubility of the powder entrainer and the skeleton agent, and to make the blank elastic so as not to crack when it leaves the mold.

[0054] Furthermore, the weight percentage of lubricant and activator is 0.2-20%;

[0055] The weight percentage of the powder entrainer is 60-93%;

[0056] The weight percentage of the matrix agent is 3-25%;

[0057] The toughening grafting agent accounts for 0.5-10% by weight.

[0058] Furthermore, in step four, the mixing equipment is a common commercially available mixing equipment, including a pressure hammer driven by an adjustable reciprocating servo cylinder and a U-shaped mixing chamber. Several heating tubes are installed in the U-shaped mixing chamber for heating. A mixing space is formed between the pressure hammer and the U-shaped mixing chamber, with a certain exhaust gap. Several spiral rotors are also installed in the mixing space for stirring.

[0059] Furthermore, the mixing process includes the following steps:

[0060] (1) Preheating of feed precursors: The temperature gradually rises to about 110℃ and the preheating time is 20-40 minutes. The stirring speed is 3-5 RPM and the pressure hammer does not press down during this stage.

[0061] The preheating stage of the feed precursor is mainly to remove the moisture in the feed precursor. The heating of the mixing chamber and slow stirring allow the moisture in the various raw materials to be discharged smoothly. At the same time, the pressure hammer does not press down during this stage, which also ensures that the various raw materials have enough space to be heated and stirred.

[0062] (2) Heating of feed precursor: In this stage, the temperature is further heated to 170°C, so that the feed precursor can absorb heat and heat up. At the same time, the pressure hammer begins to press down to help remove the air and moisture contained in the precursor. At this time, the speed is still 3-5 RPM, which can be slightly reduced compared to the preheating stage. The slight reduction in speed is mainly to prevent powder from splashing and leaking.

[0063] (3) Fine adjustment of the temperature of the feed precursor: 170℃ is the temperature at which polyoxymethylene begins to melt into mud. Therefore, after the temperature reaches 170℃, in order to avoid excessive high temperature causing the polyoxymethylene to vaporize and decompose, the movement state of the pressure hammer is observed for every 1℃ increase until it increases by another 1℃. This step is repeated until the temperature reaches 180℃.

[0064] (4) Observe whether the feed forms clumps: By observing whether the hammer moves up and down, determine that the temperature has continued to increase until the hammer has moved up and down. When the hammer is raised, sort out the material in the mixing chamber and clean the powder that overflows around the chamber.

[0065] (5) Accelerate feeding and mixing: Maintain the agglomeration temperature and press the hammer down onto the feed agglomeration, increase the rotor speed to 20-40 RPM and maintain it for 20-40 minutes to ensure that all materials are mixed so that the silicate feed is uniform;

[0066] (6) Feeding and cooling: Stop the heater and keep the hammer pressing down. Adjust the rotor speed to 3-5 RPM and wait for the temperature to drop to 165℃ to complete the feeding and mixing operation.

[0067] (7) Stop the equipment and remove the feed clumps.

[0068] Furthermore, it also includes a granulation step, where the appropriately cooled feed agglomerates are extruded and cut into small particles or powder for subsequent molding. It is not recommended to use a crusher here, as it can easily lead to uneven particle size and excessively fine particles, resulting in feed loss.

[0069] The above description is only a preferred embodiment of the present invention. Furthermore, the application field of the present invention is not limited to the above scope. It should be noted that those skilled in the art can make several improvements and additions without departing from the method of the present invention, and these improvements and additions should also be considered within the protection scope of the present invention.

Claims

1. A method for combined curing of multi-feature silicate parts, characterized in that, A pressure extrusion molding method is adopted, which includes pressing, extrusion and injection molding. The feed made of silicate mixture is heated and pressure is applied to liquefy it and injected into the mold cavity to obtain a multi-feature silicate blank. High-temperature adhesive is applied to the combined feature surfaces of individual multi-feature silicate blanks after degreasing; The above-mentioned blank is solidified into an integrated multi-feature silicate part through a thermal process; The high-temperature adhesive includes silicate powder, binder A, and the weight ratio of silicate powder, binder A and water is 1:(1-3):(1-3). The binder A is polyvinyl alcohol, polyethylene glycol or polyacrylamide. The feed is prepared from silicate powder and binder B, wherein binder B includes a lubricant and activator, a powder entrainer, a skeleton agent and a graft toughening agent; The lubricant and activator is specifically one or more of stearic acid, paraffin wax, microcrystalline wax, Fischer-Tropsch wax, polyethylene wax, ethylene bis-stearamide, and pentaerythritol stearate; the powder entrainer is copolyoxymethylene; the skeleton agent is one or more of polyethylene and polypropylene; and the graft toughening agent is one or more of ethylene-vinyl acetate copolymer and butadiene rubber.

2. The combined curing method for multi-feature silicate parts according to claim 1, characterized in that: The silicate powder in the high-temperature binder has a particle size of less than 10 μm.

3. The combined curing method for multi-feature silicate parts according to claim 2, characterized in that: The high-temperature adhesive is prepared by dissolving adhesive A in hot water at 70-90℃.

4. The combined curing method for multi-feature silicate parts according to claim 3, characterized in that: The high-temperature adhesive is applied by hand brushing, dip plating, or spraying, and the coating thickness is between 0.01 and 0.2 mm.

5. The combined curing method for multi-feature silicate parts according to any one of claims 1-4, characterized in that: The particle size of the silicate powder is in the range of 0.5-0.6 μm.

6. The combined curing method for multi-feature silicate parts according to claim 5, characterized in that: The weight percentage of the lubricant and activator is 0.2-20%; The powder entrainer accounts for 60-93% by weight; The weight percentage of the skeleton agent is 3-25%; The graft toughening agent accounts for 0.5-10% by weight.

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