What are the crack defects in the processing of automotive plastic parts?

When enterprises are processing injection molding parts, they often have some unnecessary defects due to some small reasons, which will cause certain troubles to our injection molding processing. Among these defects, the most common one is the crack defect. So, what are the factors that affect the crack defect in the processing of injection molded parts?
What are the crack defects in injection molding parts?
1. The proportion of recycled materials added to the raw materials is large, so that the shrinkage direction of the raw materials is large or the distribution of fillers is uneven;
2. The raw material plastic is polluted, volatile or poorly dried;
3. Improper demoulding design, small demoulding slope, thin product wall with sharp corners and gaps, resulting in stress concentration;
4. The pressure holding and injection time are short, and the cooling time is too long or too short;
5. The mold temperature is low or uneven, the injection speed is slow, and the pressure is low;
6. Improper molding conditions, high stress and poor ejection;
7. Improper use of release agent, uneven cooling after product release, etc.
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