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What is fiber | fiber geometry | Geometrical properties of fiber



All ordinary yarns, either man-made or natural, consist of a number of fibers or filaments. In the case of man-made fibers for textile uses, this number is usually 15 to 100 i.e. most yarns will be composed of not fewer than 15 and not more than 100. But there are, of course, some variations to these numbers which largely depends on its property and the end-products–use. The multifilament construction in yarn is adopted to confer pliability and flexibility on the yarn- a yarn composed of a number of fine filaments is much more flexible than a solid, thick filament of the same diameter as the yarn.
Textile materials are generally soft to the touch, flexible, capable of being transformed into desired shapes without resistance and durable over a reasonable period of wear. They derive these properties from fibers and yarns that form the building units arranged or interlaced in various forms. The yarn, in turn, is formed by twisting a bundle of fibers together, therefore, the   properties of the yarn, for that matter the properties of the ultimate textile structure will depend very largely on the characteristics of the fibers from which they are made and how they are made. The following are some of the most Essential And Other Desirable Properties that must be taken into account in making a choice of a fiber for use as textile material:-

  1. Dimensional and physical characteristics, such as, LENGTH, FINENESS, CROSS-SECTIONAL SHAPE, CRIMP, DENSITY.
  2. Mechanical Properties, such as, STRENGTH, ELASTICITY, EXTENSIBILITY, RIGIDITY (STIFFNESS).
  3. General properties , such as,  SURFACE CHARACTERISTICS, FRICTIONAL PROPERTIES, SOFTNESS, ENVIRONMENTAL STABILITY, RESISTANCE TO SUNLIGHT,THERMAL STABILITY, RESISTANCE TO CHEMICAL AND ORGANIC-SOLVENTS, PLIABILITY, DURABILITY, ABRASION RESISTANCE, DIMENSIONAL STABILITY, MOISTURE ABSORPTION, RESISTANCE TO BACTERIA, FUNGI, MILDEW, MOTHS, etc, STATIC CHARGE BUILD-UP, COLOUR, WETTING CHARACTERISTICS etc.
The technical significance of some of the most important properties of fibers that have a profound influence on the processing behavior and the end-use characteristics of yarns, are, FIBER LENGTH, FIBER FINENESS i.e. WIDTH, AREA OF CROSS SECTION,
WALL THICKNESS, LINEAR DENSITY,FIBER STRENGTH AND EXTENSIBILITY AND RELATED MISCELLANEOUS PROPERTIES.

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