Powder metallurgy molding, as an advanced material molding technology, occupies a vital position in modern manufacturing. It processes metal and alloy powders into products with the required shape and performance, and has many advantages such as high material utilization rate, high production efficiency, and high product accuracy.

Process

1. Powder preparation: This is the starting point of powder metallurgy. Common powder production methods include mechanical grinding, atomization, and reduction. The mechanical grinding method uses equipment such as ball mills to crush block metals into powder, which is suitable for brittle materials. The atomization method sprays liquid metal into fine droplets, which then form powder after cooling and solidifying, resulting in uniform particle size and high purity. Reduction method Metal oxides are reduced to metal powders using reducing agents, which are commonly used to produce metal powders such as iron and copper.

2. Powder mixing: In order to meet the performance requirements of products, it is often necessary to mix powders of different components uniformly. In the powder mixing process, a mixer is used to ensure that the components are evenly distributed by stirring, rolling, etc., so that the performance of the final product is consistent. For example, when producing alloy powder containing copper and zinc, uniform mixing of the powder can ensure stable alloy properties.

3. Molding: This link is an important step and determines the shape of the product. Common molding methods include compression molding, injection molding, and isostatic pressing. Compression molding uses a mold to mold the powder in the mold cavity through the action of the press. It is suitable for products with simple shapes and large lot numbers, such as gears and cams. Injection molding is a molding method in which powder mixed with a binder is injected into a mold and hardened to form it, and is suitable for the production of small precision parts with complex shapes, such as extremely small parts for mobile phones and watches. Isostatic pressing applies uniform pressure in all directions to the powder sealed in an elastic mold, which can produce products with uniform density and excellent performance, and is often used in the production of high-performance parts in the aerospace field.

4. Sintering: The strength of the green body after molding is low, so it needs to be sintered to increase its strength and density. At high temperatures, processes such as atomic diffusion, recrystallization and so on occur between powder particles, and the particles bond with each other to form a dense metal structure. According to the material and performance requirements of the product, we select different sintering atmospheres, such as vacuum, hydrogen and nitrogen. For example, the sintering of cemented carbide is usually carried out under a hydrogen protective atmosphere to prevent the oxidation of alloying elements.

5. Subsequent processing: machining, heat treatment, surface treatment, etc. Machining is to ensure dimensional accuracy and surface finish by cutting, grinding and other processes on the sintered product, heat treatment is to improve the organizational structure and performance of the product, such as quenching and tempering, and surface treatment is to increase the corrosion resistance and wear resistance of the product. Products. Electroplating, spray painting, etc.

Common products

6. Automotive parts: Powder metallurgy is widely used in automotive manufacturing, such as valve seats, piston rings, engine gears, synchronizer hubs, and transmission planetary gears. These parts are formed by powder metallurgy, which not only have high precision and stable quality, but also reduce production costs and meet the requirements of lightweight and high performance in the automotive industry.

7. Tool products: Carbide tools, drill bits, etc. Powder metallurgy process can uniformly disperse carbide particles in the cemented carbide, improve the hardness, wear resistance and cutting performance of the tool, and greatly extend the service life, and is widely used in the field of metal processing.

8. Electronic product parts: In 3C products, precision parts made by powder metallurgy can be seen everywhere, such as mobile phone vibration motors and camera parts, computer cooling fans and hard disk drive parts. These parts are small in size and require extremely high precision. Powder metallurgy molding technology exactly meets this requirement and achieves efficient production.

Due to its unique advantages, powder metallurgy molding machinery technology plays an irreplaceable role in many industries. With the continuous innovation and development of technology, its application field continues to expand, providing strong support for the high-quality development of the manufacturing industry.