Definitions /Dictionary/Glossary - nptel

and in which flexural loads produce pure bending of equal magnitude in axial and lateral
directions.
Balanced Laminate: Composite laminate whose 0° and 90° angles occur only in + or - pairs
(not necessarily adjacent) and are symmetrical around the centerline.
Ball: See Roving
Band Width: In filament winding, the width of the reinforcement as it is applied to the mandrel.
Barcol-Shore Rockwell Hardness: A material’s ability to be indented. The Rockwell method
measures the amount of penetration caused when a steel point is forced into the material. The
suffix (alphabetic letter) in the Rockwell reading describes the shape of the point and units
describe how much load was applied during the test. The letter and number cannot be separated.
Higher numbers with the same letter indicate harder materials with greater resistance to
penetration by another substance.
Bare Glass: Glass in fiber form as it flows from the bushing before a binder or sizing is applied.
Batch Oven: Large temperature-controlled oven used to heat-clean rolls of glass fiber fabric.
Batt: Felted fabrics or structures built by the interlocking action of compressing fibers, without
spinning, weaving, or knitting.
Beam: A spool on which parallel ends of single or plied yarns are wound for use in weaving or
similar processing operations.
Beaming: Operation in which many ends of yarn from a creel are combined on a section beam.
Bearing Strength: It is the maximum amount of stress that can be sustained by bearing. Also,
the point on the stress-strain curve where the tangent is equal to the bearing stress divided by n%
of the bearing hole diameter.
Bearing Stress: It is applied load in pounds divided by the bearing area. Maximum bearing
stress is the number of pounds that can be sustained, divided by the original bearing area.
Bed: The mat of chopped glass fibers deposited over a layer of resin mix on carrier film
following a chopping operation.
Bias Fabric: Warp and fill fibers placed at an angle to the length of the fabric.
Biaxial Load: Loading condition in which a laminate is stressed in two different directions in its
plane. It is also, a loading condition of a pressure vessel under internal pressure and with
unrestrained ends.
Biaxial Winding: Filament winding in which the helical band is laid in sequence, side by side,
without any fibers crossing over each other.