When it comes to powder metallurgy gear, many people don’t know it very well. It is a high-tech product with less or no chips. At the same time, the powder metallurgy gear is also leading the rapid development of powder metallurgy parts. So, what are the characteristics of powder metallurgy gears? This article will give a detailed introduction.
1、 Advantages of powder metallurgy gear
- Cost: P / M gear has low cost, high production efficiency, once forming, no need to re process gear after forming. It is suitable for the production of more products with the same shape, especially for some high gear processing costs, powder metallurgy method can be used to reduce the production cost of gears.
- Material: there is no waste material in the manufacturing process of P / M gear, and the metal loss is only 1-5%, while the metal loss can reach 80% when casting by general method. Powder metallurgy gear has a good choice for the effective utilization of resources, which is helpful to ensure the correctness and uniformity of material composition ratio.
- Processing characteristics: due to the processing characteristics of P / M gears, they can be made into oil-bearing parts to form lubrication free parts, but the effect is worse than that of oil bath lubrication, belonging to the state of boundary lubrication.
- High purity: powder metallurgy does not need to melt materials in the production process, so it does not need to mix impurities brought by crucible and deoxidizer. It is not afraid of oxidation and will not pollute the materials. It can be made into high-purity materials.
2、 Disadvantages of powder metallurgy gear
1. Poor bending and shear strength
This is because powder metallurgy mainly uses the process of recrystallization of powder at high temperature, without rolling process, resulting in no metal fiber flow in the gear, which is a kind of non oriented mechanical property, so the performance is poor.
2. Not able to transfer large torque
Due to the manufacturing process of P / M gears, the contact strength of P / M gears is low.
3. Lubrication life is short
Although the powder metallurgy gear is oil-bearing, its lubrication life is relatively short and can not be used for a long time. If it is to be used for a long time, it is still necessary to consider additional lubrication as the ordinary gear.
4. Low accuracy
The precision of powder metallurgy gear is low, and there is no way to control its precision in the process of high temperature sintering, so its precision is uncontrollable, so its transmission stability is poor. The surface roughness is also relatively large, and it is easy to produce noise in the transmission.