Definitions /Dictionary/Glossary - nptel

L/D Ratio: A term used to define an extrusion screw, which denotes the ratio of the screw length
to the screw diameter.
Lubricant: A material added to most sizing to improve the handling and processing properties
of textile strands, especially during weaving.
M-Glass: A high beryllia (BeO2) content glass designed especially for high modulus of
elasticity.
Macro: In relation to composites, denotes the gross properties of a composite as a structural
element but does not consider the individual properties or identity of the constituents.
Macro-strain: The mean strain over any finite gage length of measurement which is large in
comparison to the material's inter-atomic distance.
Male Mold: A convex mold where the concave surface of the part is precisely defined by the
mold surface.
Mandrel: A form fixture or male mold used for the base in the production of a part by lay-up,
filament winding or braiding.
Mass: The quantity of matter contained in a specific body. In reference to polyesters, mass is
measured in mils or inches thickness of a film or casting.
Master (Plug): The permanent tool used to build molds for the manufacture of fiberglass parts.
Mat: A fibrous material consisting of randomly oriented chopped or swirled filaments loosely
held together with a binder.
Mat Binder: Resin applied to glass fiber and cured during the manufacture of mat, to hold the
fibers in place and maintain the shape of the mat.
Matched Die Molding: The technique for producing long runs of identical parts with two
finished sides.
Matched Metal Molding: A reinforced plastics manufacturing process in which matching male
and female metal molds are used to form the part, with time, pressure and heat.
Matched Molds: Two or more tools arranged in a set as a male and female mold. Normally
used in a press.
Matched Metal Molding: A reinforced plastics manufacturing process in which matching male
and female metal molds are used ( similar to compression molding) to form the part - as opposed
to low pressure laminating or spray-up.
Material Acceptance: The testing of incoming material to ensure that it meets requirements.