What are the methods for powder preparation in powder metallurgy process- Ningbo Jiangbei District Cicheng Pneumatic Components Factory.

Powder Metallurgy (PM) is an advanced material preparation technology that is widely used in the manufacture of metal and non-metal products with specific properties and shapes. The process covers multiple links such as powder preparation, mixing, forming, sintering and post-processing. Among them, the powder preparation stage is particularly critical, which directly affects the stability of subsequent processes and the performance of the final product.

In the preparation process of powder metallurgy, the oxide reduction method is a commonly used metal powder preparation technology. This method reduces metal oxides to metal powders under high temperature conditions by reducing agents such as hydrogen, carbon monoxide or carbon. The main advantage of the oxide reduction method is that it can obtain high-purity metal powders and the process is relatively simple. However, this method consumes a large amount of reducing agents during the reduction process, and may release harmful gases, which has a certain impact on the environment. Therefore, corresponding environmental protection measures need to be taken when it is applied.

Atomization is another important metal powder preparation technology, which mainly sprays molten metal into a high-speed airflow to rapidly cool and solidify it to form powder. According to different spraying methods, atomization can be divided into double-flow atomization, vacuum atomization, rotating electrode atomization and mechanical force atomization. Among them, double-flow atomization and vacuum atomization are the most widely used technologies. Double-flow atomization achieves rapid cooling and solidification through the interaction of high-speed airflow and molten metal; while vacuum atomization is carried out in a vacuum environment to prevent metal powder from oxidation and contamination during the preparation process. The metal powder prepared by atomization has fine particle size, uniform distribution, and high purity and activity.

Electrolysis is a technology for preparing metal powder by electrolyzing metal salt solution. During the electrolysis process, metal ions obtain electrons on the cathode and are reduced to metal powder. The main advantage of electrolysis is that it can prepare high-purity metal powder and the process control is relatively easy. However, this method has high energy consumption and relatively low preparation efficiency, especially when dealing with some refractory metals or active metals, the preparation difficulty increases significantly.

The rotating electrode method is to use a metal rod as an anode and perform electrolysis under high-speed rotation conditions to gradually peel off the metal and form powder. The metal powder prepared by this method has fine particle size, uniform distribution, and high purity and activity. The advantage of the rotating electrode method is that it can produce high-quality metal powders, and the process is easy to control, but it also consumes a lot of electricity and metal raw materials, and the preparation efficiency is relatively low.

The mechanical crushing method is to crush bulk metals or alloys into powders by mechanical force. This method usually uses equipment such as ball mills, vibration mills or air flow mills to produce metal powders of the required particle size through processes such as crushing, grinding and screening. The advantage of the mechanical crushing method is that the equipment investment is relatively low and it is suitable for large-scale production, but the purity of the metal powder prepared by it may be affected by the raw materials.