Effect Of Injection Molding Process On Surface Finish

Surface finish largely depends on the chemical composition of the materials used and the design of the core of the injection mold.

Material selection

Each material has different physical and chemical properties. Indicators such as material melting temperature also play a vital role in the surface finish of the product. Additives used in the material will also affect the surface finish of the article.

For example, if a shiny surface is required and a crystalline resin material is used, a higher melt temperature is required to reduce roughness and increase gloss to the part. In the case of selecting additives, a deep understanding of the materials is required to know which additives to add. It is worth noting that a simple polished mold surface does not necessarily imply a high level of gloss. Factors such as mold design, molding conditions, and materials used will affect the quality of gloss.

It’s not just the materials used that matter. The material of the injection mold also has an important influence on the surface quality. The selected mold steel needs to have a very high hardness.

Injection temperature and speed

The speed of injection of the molten material has a great effect on obtaining a proper quality finish. Rapid filling of the mold cavity can reduce the visibility of weld marks, and improve surface finish and overall appearance. High injection speed, combined with higher mold and melt temperatures, improves surface smoothness.

Post time: Apr-07-2021