M - Polymer Processing Glossary of Terms

Matte finish - A surface which displays no gloss when observed at any angle.
Mean - See Average
Melt Flow Index - The amount, in grams, of a thermoplastic resin which can be forced through a 0.0825 inch orifice when subject to 2,160 grams force for ten minutes at 230°C, per ATSM D1238
Metallizing - Applying a thin coating of metal to a non-metallic surface.
Metering Zone - The final zone of an injection barrel or screw, at which the melt is advanced at a uniform rate to the screw tip.
Mold - The cavity or matrix of cavities into which plastic melt is placed and takes form.
Mold Components - Parts that make up a mold and determine how a mold will be operated.
Mold Frame - Series of metal plates which support mold components.
Multi-cavity Mold - A mold with two or more cavities.

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