How to Make Powder Sintered Oil Bearing

How to Make Powder Sintered Oil Bearing

The powder sintered oil bearing is suitable for mass production without cutting, low cost, low noise, lubrication, not easy to burn, high friction coefficient, low mechanical strength, and is not suitable for the production of a small number of varieties. So, how to make powder sintered oil bearing? Technicians from Zhongwei Precision Powder Metallurgy Factory in Qinhuangdao will introduce:

The manufacturing process of powder sintered oil bearing includes powder raw material inspection - powder raw material preparation and mixing - compression forming - sintering - shaping - oil treatment - product inspection

The metal powder in the first stage can be used to make copper powder, iron powder, aluminum powder, zinc powder, tin powder. Usually, a certain proportion of stone powder needs to be added, and the necessary powder materials are processed by chemical method, liquid pulverization method, electrolysis method and mechanical pulverization method.

The second stage: powder preparation. Due to the imperfect powder preparation conditions in this stage, many problems occurred in the pressing and sintering process, wasting time and energy. To protect the mold, 10% zinc stearate is smoothly added to the powder. Mix and mix various powders according to the design proportion, and pay attention to prevent heavy metal powder from sinking and light graphite powder from floating. In order to smoothly fill the mold with powder, the mixed powder can be made into granules to make it have good fluidity.

powder metallurgy

The third stage: stamping. In the manufacturing process of powder sintered oil bearing, the stamping process is very important. During compression forming, the contact between powder particles increases rapidly, the porosity of porous body decreases, and the strength increases. Generally, the compound movement stamping mode of up and down two-way compression is adopted. The forming pressure of copper materials is 1-3t/cm2. The higher the forming pressure is, the greater the product density is, the smaller the size thermal deformation during sintering is, and the higher the product strength is. However, the lower the porosity of the sintered body is, the smaller the oil content is. The die positioning is very important in the stamping process, which does not ensure that the product is concentric inside and outside, and it is difficult to shape after sintering.

The fourth stage is the sintering stage. The pressed powder achieves the combination between the powders in the sintering process to obtain the necessary strength. The sintering temperature is generally lower than the melting point of the powder, and some are insoluble, which is called liquid phase sintering. After the powder is completely melted, it is called solid phase sintering. The sintering mechanism is diffusion between the solid phase and solid phase of the powder, and it is integrated from the contact part of the powder particles. Therefore, the material of powder sintered oil-bearing is oil-bearing porous composite material formed by powder with different weight in the state of retaining its own physical phase.

The fifth stage: the size change of the sintered body during shaping and sintering varies with the secretion type, particle size forming pressure, sintering temperature and time. After sintering, it is necessary to rectify the change of the size and shape of the sintered body. Shaping is also realized by pressing the die. In order to prolong the life of the die, the shaping process can also be put after the oil treatment.

The last step is oil treatment. Oil treatment includes immersion in oil heated to 80-120 ° C under atmospheric pressure for about 1h, and injection of lubricating oil heated to about 50 ° C under vacuum for thermal insulation, and finally cooling in the atmosphere. Powder sintered oil bearing basic manufacturing.

As an important mechanical basic component, it is widely used in automobile, audio equipment and meters, electronic instruments and other industrial fields. So far, powder sintered oil bearing can be seen everywhere in the bearing market, playing an irreplaceable role. Now do you know how to make powder sintered oil bearing! Friends with demand for powder metallurgy products can call Zhongwei Precision.