Definitions /Dictionary/Glossary - nptel

Cell: The vertical plane of doffs on a pallet. A pallet may be constructed for 4- or 12-end run-out
depending on application.
C-Glass: Glass with a soda-lime-borosilicate composition that maintains chemical stability in
corrosive environments.
Chalking: It is the surface phenomenon indicating degradation of a cosmetic surface. Chalking
is a powdery film that appears lighter than the original color.
Chemical Size: A surface finish applied to the fiber that contains some chemical constituents
other than water.
Choppability: The ease of chopping/cutting the glass fibers to a uniform length.
Clamping Pressure: In injection molding and transfer molding, the pressure that is applied to
the mold to keep it closed in opposition to the fluid pressure of the compressed molding material.
Cloth: Fiberglass reinforcement made by weaving strands of glass fiber yarns.
Clump: A group of chopped bundles of glass fibers that has collected on the SMC machine and
then fallen into the bed of glass. The clump produces areas of high glass content which may not
wet-through.
Coefficient of Thermal Expansion (CTE): How much a material’s shape will change per each
degree of temperature fluctuation.
Cold Flow: Distortion that occurs in a material under continuous load within its working
temperature range and without a phase or chemical change.
Collet: A spool on which the gathered strands from the bushing are wound for further
processing.
Compaction: Applying a temporary vacuum bag and vacuum to remove trapped air and
compact the lay-up; also removing air in SMC machines prior to roll-up.
Compatibility: The ability of two or more substances to be combined in order to form a
homogeneous composition of useful plastic properties; for example, the suitability of a sizing or
finish for use with certain general resin types.
Composite: Chemical or mechanical bonding of dissimilar materials such as glass fiber and
polyester resin, whose cumulative properties are superior to the individual materials.
Composite Material: A combination of two or more materials (reinforcing elements, fillers, and
composite matrix binder). Although they act in concert, the constituents retain their identities;
that is, they do not dissolve or merge completely into one another. Normally, the components can
be physically identified and exhibit an interface between one another.