What are defects in plastics ?

Question

Accepted Answer

Defects in plastics refer to imperfections or flaws that affect the quality and performance of plastic materials.

Sink marks: Depressions or dents on the surface caused by uneven cooling or inadequate material flow.
Warping: Distortion or bending of the plastic part due to uneven cooling or residual stresses.
Flash: Excess material that protrudes from the mold joint, caused by poor mold design or excessive injection pressure.
Short shots: Incomplete filling of the mold cavity, resulting in a part with missing sections.
Bubbles or voids: Air pockets trapped within the plastic, caused by inadequate venting or excessive moisture content.
Cracks: Fractures or splits in the plastic, often caused by stress concentration or improper cooling.
Delamination: Separation of layers within the plastic, typically caused by poor adhesion between layers.
Contamination: Presence of foreign particles or impurities in the plastic material, leading to reduced strength or appearance issues.

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