Factors Affecting Shrinkage of MIM in Metal Powder Injection Molding

With the continuous improvement of precision requirements for metal powder injection molding, in addition to correct material selection and modification, Guangdong Dahong New Materials believes that it is very important to correctly select conditions and reasonably analyze the relationship between shrinkage and production, especially shrinkage, which seriously affects quality. The shrinkage rate is mainly affected by many factors. Dahong New Materials generally divides the factors affecting the shrinkage rate of metal powder injection molding into the following aspects:

1. Resin pressure: it has a great influence on the shrinkage of metal powder injection molding. If the resin pressure is large, the shrinkage will become smaller, and the size of MIM material products will be larger. Metal powder injection molding manufacturers have found that even in the same the first mock examination cavity, the resin pressure varies according to the shape of the products, so there is a difference in shrinkage. In the case of multi cavity mold, the resin pressure in each cavity tends to be different, resulting in different shrinkage of each cavity.

2. Mold temperature: whether it is non crystalline resin or crystalline resin, if the mold temperature is high, the shrinkage will increase. The die temperature of Dahong New Material shall be maintained at a specific temperature during precision forming. MIM technical experts remind everyone to pay attention to the cooling circuit design when designing the mold.

3. Gate sectional area: Generally speaking, when the gate sectional area is changed, the shrinkage also changes. Shrinkage decreases with the increase of gate size, which is related to the fluidity of resin.

4. Product wall thickness: the product wall thickness also affects the yield. During metal powder injection molding, Dahong New Materials found that for amorphous resin, because the resin has different influences on the shrinkage rate of wall thickness, the shrinkage rate is also large when the wall thickness is large, otherwise, the shrinkage rate becomes smaller. For crystalline resin, the wall thickness change should be avoided. In the case of multi cavity mold, if the cavity wall thickness is different, the shrinkage will also be different.

5. Reinforcing material content: when using fiberglass reinforced resin, the more fiberglass is added, the smaller the shrinkage rate. The shrinkage rate of metal powder injection molding in the flow direction is smaller than the horizontal shrinkage rate. The difference between Dahong New Material and resin is large. In order to prevent distortion and warpage, we remind you to consider the gate shape, gate position and gate number.

These are the factors that affect the shrinkage of metal powder injection molding. I hope the introduction of these factors can help you avoid the shrinkage problem caused by these problems during metal powder injection molding. If you have other problems, please come to consult the technical team of Dahong New Materials!

With the continuous improvement of precision requirements for metal powder injection molding, in addition to correct material selection and modification, Guangdong Dahong New Materials believes that it is very important to correctly select conditions and reasonably analyze the relationship between shrinkage and production, especially shrinkage, which seriously affects quality. The shrinkage rate is mainly affected by many factors. Dahong New Materials generally divides the factors affecting the shrinkage rate of metal powder injection molding into the following aspects:

1. Resin pressure: it has a great influence on the shrinkage of metal powder injection molding. If the resin pressure is large, the shrinkage will become smaller, and the size of MIM material products will be larger. Metal powder injection molding manufacturers have found that even in the same the first mock examination cavity, the resin pressure varies according to the shape of the products, so there is a difference in shrinkage. In the case of multi cavity mold, the resin pressure in each cavity tends to be different, resulting in different shrinkage of each cavity.

2. Mold temperature: whether it is non crystalline resin or crystalline resin, if the mold temperature is high, the shrinkage will increase. The die temperature of Dahong New Material shall be maintained at a specific temperature during precision forming. MIM technical experts remind everyone to pay attention to the cooling circuit design when designing the mold.

3. Gate sectional area: Generally speaking, when the gate sectional area is changed, the shrinkage also changes. Shrinkage decreases with the increase of gate size, which is related to the fluidity of resin.

4. Product wall thickness: the product wall thickness also affects the yield. During metal powder injection molding, Dahong New Materials found that for amorphous resin, because the resin has different influences on the shrinkage rate of wall thickness, the shrinkage rate is also large when the wall thickness is large, otherwise, the shrinkage rate becomes smaller. For crystalline resin, the wall thickness change should be avoided. In the case of multi cavity mold, if the cavity wall thickness is different, the shrinkage will also be different.

5. Reinforcing material content: when using fiberglass reinforced resin, the more fiberglass is added, the smaller the shrinkage rate. The shrinkage rate of metal powder injection molding in the flow direction is smaller than the horizontal shrinkage rate. The difference between Dahong New Material and resin is large. In order to prevent distortion and warpage, we remind you to consider the gate shape, gate position and gate number.

These are the factors that affect the shrinkage of metal powder injection molding. I hope the introduction of these factors can help you avoid the shrinkage problem caused by these problems during metal powder injection molding. If you have other problems, please come to consult the technical team of Dahong New Materials!