F - Polymer Processing Glossary of Terms

Feed zone - Zone on injection screw directly below hopper. Plastic is pre-heated in this zone, not melted.
Filler - A substance added to the plastic to make it less costly. Some fillers also improve mechanical properties.
Finish - The ultimate surface of a plastic part.
Flash - The thin, surplus web of material which is forced into crevices between mating surfaces during a molding operation, and which remains attached to the molded article.
Flow lines - Wavy surface appearance caused by improper flow of the resin into the mold.
Fluorescent - Organic dyes or pigments which may be blended into inks to provide a luminescent or fluorescent appearance typical of the "neon" colors.
Frictional heating - See Shear Heating

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