Hard alloy and processing method

Abstract

The invention relates to the technical field of hard alloy, in particular to a hard alloy and a machining method. The machining method comprises the following steps that tungsten carbide, cobalt and titanium carbide are weighed according to a preset proportion; tungsten carbide, cobalt and titanium carbide are put into a ball mill to be mixed, and a mixture is obtained; performing granulation on the mixture; the granulated raw materials are put into a mold to be shaped, and a green body is obtained; sintering the green body to obtain a semi-finished product; and cutting, grinding and polishing the semi-finished product to obtain the hard alloy. By optimizing the raw material ratio, the hardness, toughness and bending strength of the hard alloy are remarkably improved, and the hard alloy can still keep good use performance under various severe working conditions. The production efficiency is improved, and the production period is shortened. Raw material inspection and finished product detection are enhanced, stable and reliable product quality is ensured, diversified requirements of customers are met, and therefore the problem that existing hard alloy is low in comprehensive performance is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of cemented carbide, and in particular to a cemented carbide and a processing method thereof. Background Art

[0002] Cemented carbide is known as the "teeth of industry". It is a high-efficiency tool material and structural material. It is mainly used in the field of precision machining tool technology for CNC machine tools. It can also be used in the field of wear-resistant technology of molds and engineering machinery such as rock drilling, mining, and construction. It has played an important role in promoting industrial development and scientific and technological progress.

[0003] At present, the existing cemented carbide has low comprehensive performance and poor corrosion resistance, which leads to time-consuming, labor-intensive and high cost in subsequent processing. Summary of the invention

[0004] The purpose of the present invention is to provide a cemented carbide and a processing method, aiming to solve the problem of low comprehensive performance of existing cemented carbide.

[0005] To achieve the above object, in a first aspect, the present invention provides a cemented carbide processing method, comprising the following steps:

[0006] Weigh tungsten carbide, cobalt and titanium carbide according to a preset ratio;

[0007] Putting tungsten carbide, cobalt and titanium carbide into a ball mill and mixing them to obtain a mixture;

[0008] granulating the mixture;

[0009] The granulated raw materials are placed in a mold for shaping to obtain a green body;

[0010] Sintering the green body to obtain a semi-finished product;

[0011] The semi-finished product is cut, ground and polished to obtain cemented carbide.

[0012] Among them, in “weighing tungsten carbide, cobalt and titanium carbide according to a preset ratio”, the preset ratio is 88:4:8.

[0013] The process of “putting tungsten carbide, cobalt and titanium carbide into a ball mill and mixing them to obtain a mixture” includes the following steps:

[0014] Pour the weighed tungsten carbide, cobalt and titanium carbide powders into the container of the ball mill, and add appropriate amounts of ball milling media and dispersant to mix;

[0015] The mixture was removed from the ball mill and dried.

[0016] Wherein, in "granulating the mixture", the following steps are included:

[0017] The dried mixture is placed in a granulator for granulation;

[0018] The granulated material is screened.

[0019] The step of “putting the granulated raw material into a mold for shaping to obtain a green body” includes the following steps:

[0020] Select the mold;

[0021] The granulated raw materials are placed in a mold and pressed by a pressing machine to obtain the desired green body shape;

[0022] After the blank is taken out, it is inspected and trimmed.

[0023] Among them, the step of “sintering the green body to obtain a semi-finished product” includes the following steps:

[0024] After setting the sintering parameters, the green body is placed in the sintering furnace for sintering;

[0025] The sintered green body is taken out for cooling to obtain a semi-finished product.

[0026] In a second aspect, a cemented carbide is prepared by the cemented carbide processing method described in the first aspect, comprising tungsten carbide, cobalt and titanium carbide.

[0027] A cemented carbide processing method of the present invention comprises the following steps: weighing tungsten carbide, cobalt and titanium carbide according to a preset ratio; putting tungsten carbide, cobalt and titanium carbide into a ball mill for mixing to obtain a mixture; granulating the mixture; putting the granulated raw materials into a mold for shaping to obtain a blank; sintering the blank to obtain a semi-finished product; cutting, grinding and polishing the semi-finished product to obtain a cemented carbide. The present invention significantly improves the hardness, toughness and bending strength of cemented carbide by optimizing the raw material ratio, so that it can still maintain good performance under various harsh working conditions. The application of high-temperature sintering technology makes the microstructure of cemented carbide material more dense and uniform, and further improves its comprehensive mechanical properties. Adding an appropriate amount of corrosion-resistant additives and forming a protective film on the surface of cemented carbide effectively improves the corrosion resistance of the material and prolongs its service life. The improved cemented carbide material has higher hardness and toughness, so that tool wear and cutting force can be reduced in subsequent processing, and processing efficiency and precision can be improved. The smoothness and uniformity of the material surface are improved, reducing the workload of subsequent grinding and polishing, and further reducing processing costs. The use of efficient mixing, molding and sintering equipment, as well as strict process control, improves production efficiency and shortens production cycles. Strengthening raw material inspection and finished product testing ensures stable and reliable product quality and meets the diverse needs of customers, thus solving the problem of low comprehensive performance of existing cemented carbide. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 The present invention provides a flowchart of a cemented carbide processing method.

[0030] Figure 2 This is a flow chart of mixing tungsten carbide, cobalt and titanium carbide in a ball mill to obtain a mixture.

[0031] Figure 3 It is a flow chart for granulating the mixture.

[0032] Figure 4 It is a flow chart of putting the granulated raw materials into a mold for shaping to obtain a green body.

[0033] Figure 5 This is a flow chart of sintering the green body to obtain a semi-finished product. DETAILED DESCRIPTION

[0034] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0035] See also Figures 1 to 5 In a first aspect, the present invention provides a cemented carbide processing method, comprising the following steps:

[0036] S1 weighs tungsten carbide, cobalt and titanium carbide according to a preset ratio;

[0037] The preset ratio is 88:4:8.

[0038] Specifically, first, according to the ratio of 88:4:8, use weighing equipment to weigh the required mass of tungsten carbide, cobalt and titanium carbide powder respectively, and ensure that the weighing of each raw material is accurate and avoid cross contamination.

[0039] S2: putting tungsten carbide, cobalt and titanium carbide into a ball mill and mixing them to obtain a mixture;

[0040] S21: pouring the weighed tungsten carbide, cobalt and titanium carbide powders into a container of a ball mill, and adding appropriate amounts of ball milling media and dispersants to mix;

[0041] Specifically, weighed tungsten carbide, cobalt and titanium carbide powders are poured into the container of the ball mill; an appropriate amount of ball milling media (such as alumina balls, zirconia balls, etc.) and an appropriate amount of anhydrous ethanol are added as a dispersant. The speed, milling time and amount of ball milling media are set to ensure uniform mixing and fine powder particle size.

[0042] S22 takes the mixture out of the ball mill and performs drying treatment.

[0043] Specifically, after the ball milling is completed, the mixture is taken out from the ball mill and dried to remove the solvent and moisture.

[0044] S3 granulates the mixture;

[0045] S31 putting the dried mixture into a granulator for granulation;

[0046] Specifically, the dried mixture is evenly poured into the hopper of the granulator. During the addition process, the addition speed is controlled to avoid too much or too little accumulation of the mixture in the hopper, which affects the granulation effect; after confirming that all preparations are ready, the granulator is started. The mixture is evenly dispersed under the action of the agitator and sprayed out in the form of mist through the nozzle. At the same time, the hot air system inside the machine provides suitable temperature and humidity conditions to promote the formation and solidification of particles. When the granulation process is completed, the granulator is turned off and the granulation product is collected.

[0047] S32 screens the granulated material.

[0048] Specifically, after the granulation product is collected, the screening equipment is prepared; the granulation product is poured into the feed port of the screening equipment, and the screening machine is started. During the screening process, the particles are subjected to vibration and friction on the screen and are gradually separated into particles of different sizes. After the screening is completed, the particles of different sizes are collected separately. Finally, the screened products are inspected and tested.

[0049] S4: placing the granulated raw materials into a mold for shaping to obtain a green body;

[0050] S41 selects the mold;

[0051] Specifically, the shape, size and tolerance range of the required blank are determined according to the design requirements and process specifications of the final product. According to the shape and size of the blank, the appropriate mold type is selected, and the mold surface quality, dimensional accuracy, and whether there are cracks, wear and other defects are checked.

[0052] S42: placing the granulated raw material into a mold and subjecting the raw material in the mold to pressure molding by a pressing machine to obtain a desired green body shape;

[0053] Specifically, place the selected mold on the workbench of the press, adjust the position and angle of the mold to ensure that it is aligned with the pressure head of the press, fill the granulated raw materials into the mold evenly, start the press, and press the raw materials in the mold. During the pressurization process, observe the changes in the mold and raw materials, and adjust the pressing parameters in time to obtain the desired shape and size of the green body. When the pressing is completed, turn off the press and wait for the mold to cool. Then, use a release agent or other tools to remove the green body from the mold. During the demolding process, avoid damaging or deforming the green body.

[0054] S43 takes out the blank and inspects and trims it.

[0055] Specifically, the removed blank is inspected for appearance to see if its surface is flat and smooth, and if there are defects such as cracks and bubbles. At the same time, the size and shape of the blank are measured to ensure that it meets the design requirements. Blanks with defects or that do not meet the requirements are trimmed.

[0056] S5 sintering the green body to obtain a semi-finished product;

[0057] S51 sets the sintering parameters and places the green body into a sintering furnace for sintering;

[0058] Specifically, the sintering temperature is usually between 1000℃ and 1500℃, and the sintering time is 1h-2.5h. Before formal sintering, the green body is preheated to remove moisture and gas inside the green body and reduce defects during the sintering process. The green bodies are evenly placed in the heating area of ​​the sintering furnace, ensuring that there is enough space between the green bodies for even heat transfer. At the same time, according to the model and specifications of the sintering furnace, adjust the inert gas in the furnace, etc. After setting the sintering parameters, start the control system of the sintering furnace and start the sintering process.

[0059] S52 takes out the sintered green body and performs cooling treatment to obtain a semi-finished product.

[0060] Specifically, after sintering, when the temperature in the furnace drops to a safe range, open the sintering furnace door and use tools to take the green body out of the furnace. During the removal process, avoid mechanical damage to the green body. Place the taken green body in a cooling device for rapid cooling or natural cooling. After cooling, perform an appearance inspection and dimensional measurement on the green body, and record relevant data for subsequent analysis and improvement.

[0061] S6 cuts, grinds and polishes the semi-finished products to obtain cemented carbide.

[0062] Specifically, a diamond tool or a laser cutting machine is used to cut the sintered green body into a desired shape and size; a grinding wheel is used to perform rough and fine grinding on the cut green body to remove cutting marks and surface defects; and a polishing agent or a polishing wheel and other equipment are used to polish the ground green body.

[0063] Embodiment 1

[0064] Accurately weigh tungsten carbide, cobalt and titanium carbide powders in a ratio of 88:4:8 to ensure the quality of each raw material is accurate, and use independent weighing equipment and containers to avoid cross contamination.

[0065] Pour the weighed raw materials into a ball mill, add an appropriate amount of alumina balls as the ball milling medium and an appropriate amount of anhydrous ethanol as a dispersant. Set the ball mill speed to 200 rpm and the ball milling time to 4 hours to ensure uniform mixing and fine powder particle size. After the ball milling is completed, take out the mixture and dry it to remove the solvent and moisture.

[0066] Pour the dried mixture evenly into the hopper of the granulator, and control the addition speed to avoid accumulation. Start the granulator, the mixture is evenly dispersed under the action of the agitator and sprayed out in the form of mist through the nozzle. The hot air system provides suitable temperature and humidity conditions to promote the formation and solidification of particles. After the granulation is completed, the granulation product is collected and sieved to obtain particles of different particle sizes.

[0067] According to the shape and size of the required green body, select a suitable mold and check its quality. Fill the granulated raw materials evenly into the mold, place it on the workbench of the press, and adjust the mold position. Start the press to press and form the green body to obtain the required shape and size. After the pressing is completed, turn off the press and wait for the mold to cool, then use a release agent to remove the green body from the mold.

[0068] Set the sintering temperature to 1200℃ and the sintering time to 2 hours. Preheat the green body before formal sintering. Place the green body evenly in the heating area of ​​the sintering furnace and adjust the inert gas atmosphere in the furnace. Start the control system of the sintering furnace and start the sintering process. After sintering, wait until the temperature in the furnace drops to a safe range, take out the green body and quickly cool it.

[0069] The sintered green body is cut into the required shape and size using a diamond tool, and then rough and fine grinding is performed to remove cutting marks and surface defects. Finally, the ground green body is polished with a polishing agent to obtain a finished cemented carbide product.

[0070] Embodiment 2

[0071] Zirconia balls were used as the ball milling media, and the ball milling time was adjusted to 6 h to obtain a finer powder particle size.

[0072] The sintering temperature was set to 1300 °C, the sintering time was set to 1.5 h, and the inert gas flow rate in the furnace was adjusted to ensure the best sintering environment.

[0073] During cutting and grinding, finer diamond tools and grinding wheels are used to achieve higher surface quality and precision.

[0074] Embodiment 3

[0075] When weighing the raw materials, each raw material is subjected to more stringent quality control and testing to ensure that its purity and composition meet the requirements.

[0076] During the press forming process, more advanced pressing techniques and equipment are used to obtain higher green body density and more uniform microstructure.

[0077] During the sintering process, a more precise temperature control system and more optimized sintering parameters are used to ensure the best sintering effect and performance.

[0078] In response to the current problems of low comprehensive performance and poor corrosion resistance of cemented carbide, this embodiment improves the performance of cemented carbide in the following ways: Optimize the raw material ratio: By accurately weighing and mixing tungsten carbide, cobalt and titanium carbide powders, the uniformity and purity of the raw materials are ensured, thereby improving the strength and corrosion resistance of the cemented carbide. Improve the ball milling and granulation process: By optimizing the ball milling parameters and granulation conditions, particles with uniform particle size and regular shape are obtained, and the sintering performance and yield of the cemented carbide are improved. Optimize the pressing and sintering process: By improving the pressing technology and sintering parameters, the density of the blank and the uniformity of the microstructure are improved, thereby improving the mechanical properties and corrosion resistance of the cemented carbide. Fine processing: By adopting more sophisticated cutting, grinding and polishing processes, the surface quality and precision of the cemented carbide are improved, and the difficulty and cost of subsequent processing are reduced.

[0079] In a second aspect, a cemented carbide is prepared by the cemented carbide processing method described in the first aspect, comprising tungsten carbide, cobalt and titanium carbide.

[0080] Beneficial effects:

[0081] 1. A cemented carbide and processing method provided by the present invention optimizes the raw material ratio: by accurately weighing and mixing tungsten carbide, cobalt and titanium carbide powders, the uniformity and purity of the raw materials are ensured, thereby improving the strength and corrosion resistance of the cemented carbide.

[0082] 2. The present invention provides a cemented carbide and processing method to improve the ball milling and granulation process: by optimizing the ball milling parameters and granulation conditions, particles with uniform particle size and regular shape are obtained, thereby improving the sintering performance and yield rate of cemented carbide.

[0083] 3. The present invention provides a cemented carbide and processing method to optimize the pressing and sintering process: by improving the pressing technology and sintering parameters, the density of the green body and the uniformity of the microstructure are improved, thereby improving the mechanical properties and corrosion resistance of the cemented carbide.

[0084] 4. A cemented carbide and processing method provided by the present invention: Fine processing: By adopting more sophisticated cutting, grinding and polishing processes, the surface quality and precision of the cemented carbide are improved, and the difficulty and cost of subsequent processing are reduced.

[0085] The above disclosure is only a preferred embodiment of a cemented carbide and a processing method of the present invention. Of course, this cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A method for processing cemented carbide, characterized in that: The following steps are involved: Weigh tungsten carbide, cobalt and titanium carbide according to a preset ratio; Putting tungsten carbide, cobalt and titanium carbide into a ball mill and mixing them to obtain a mixture; granulating the mixture; The granulated raw materials are placed in a mold for shaping to obtain a green body; Sintering the green body to obtain a semi-finished product; The semi-finished product is cut, ground and polished to obtain cemented carbide.

2. The method for processing cemented carbide according to claim 1, characterized in that: In "weighing tungsten carbide, cobalt and titanium carbide according to a preset ratio", the preset ratio is 88:4:

8.

3. The method for processing cemented carbide according to claim 1, characterized in that: In "putting tungsten carbide, cobalt and titanium carbide into a ball mill and mixing them to obtain a mixture", The following steps are involved: Pour the weighed tungsten carbide, cobalt and titanium carbide powders into the container of the ball mill, and add appropriate amounts of ball milling media and dispersant to mix; The mixture was removed from the ball mill and dried.

4. The method for processing cemented carbide according to claim 1, characterized in that: In "granulating the mixture", the following steps are included: The dried mixture is placed in a granulator for granulation; The granulated material is screened.

5. The method for processing cemented carbide according to claim 1, characterized in that: In "putting the granulated raw material into a mold for shaping to obtain a green body", the following steps are included: Select the mold; The granulated raw materials are placed in a mold and pressed by a pressing machine to obtain the desired green body shape; After the blank is taken out, it is inspected and trimmed.

6. The method for processing cemented carbide according to claim 1, characterized in that: In "sintering the green body to obtain a semi-finished product", the following steps are included: After setting the sintering parameters, the green body is placed in the sintering furnace for sintering; The sintered green body is taken out for cooling to obtain a semi-finished product.

7. A cemented carbide prepared by the cemented carbide processing method according to any one of claims 1 to 6, characterized in that: These include tungsten carbide, cobalt and titanium carbide.

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