Definitions /Dictionary/Glossary - nptel

etc., in woven or non-woven form. To be effective, the reinforcing material must form a strong
adhesive bond with the resin. ("Reinforcement" should not be used synonymously with "filler").
Reinforcing Cord: Loosely twisted cord made up from rovings and designed for incorporation
in moldings where edge reinforcement and high strength ribs are necessary.
Release Agent: A material which is applied in a thin film to the surface of a mold to keep the
resin from bonding to the mold. See Mold Release Agent.
Release Film: An impermeable film layer that does not bond to the composite during cure.
Resilience: A property of a material which is able to do work against restraining forces during
return from a deformed condition.
Resin: An organic polymer or pre-polymer used as a matrix to contain the fibrous reinforcement
in a composite material or as an adhesive. This organic matrix may be a thermoset or a
thermoplastic, and may contain a wide variety of components or additives to influence; handleability,
processing behavior and ultimate properties.
Resin Content: See Matrix content.
Resin Starved Area: Area of composite part where the resin has a non-continuous smooth
coverage of the fiber.
Resin System: A mixture of resin, with ingredients such as catalyst, initiator, diluents, etc.
required for the intended processing and final product.
Resin-Rich Area: Space which is filled with resin and lacking reinforcing material.
Resin-Starved: Areas of insufficient resin, usually identified by low gloss, dry spots or fiber
show.
Resin Tearing: Separation of pigments from the polyester, usually seen as black wavy lines.
Resin Transfer Molding (RTM): A molding process in which catalyzed resin is transferred into
an enclosed mold into which the fiber reinforcement has been placed; cure normally is
accomplished without external heat. RTM combines relatively low tooling and equipment costs
with the ability to mold large structural parts.
Room Temperature Ambient (RTA): 1) an environmental condition of 73±5°F (23±3°C) at
ambient laboratory relative humidity; 2) a material condition where, immediately following
consolidation/cure, the material is stored at 73±5°F (23±3°C) and at a maximum relative
humidity of 60%.