Carbon & Fiberglass Sales :: Terminology


Carbon, Kevlar, Fiberglass Terminology:

Bi-Directional: Fabrics woven this way have uniform polar or multi-directional strength patterns and use identical or similar types of material in both the WARP and FILL.

The COUNT is related to the PICS: Let’s say a fabric has a COUNT of 12 x 8 PICS; this means a COUNT of 12 pics-per-inch in the WARP, and a COUNT of 8 pics-per-inch in the FILL. COUNT refers to the number of fibers or pics in each inch of woven fabric.

Ends: "ENDS" refer only to the fibers in the WARP direction of composite fabrics. So we say, "How many WARP ENDS does the fabric have?" The term ENDS is referred to when you want to know what is the WARP "COUNT" of a fabric... Meaning, if there are 12 WARP ENDS in a fabric, then there are 12 fibers per-inch of width of the fabric, so it has a COUNT of "12-ENDS per-inch"

Fabric: The plain, individual fibers are woven into a “FABRIC”. Carbon FABRICS have terms which describe various qualities of the weave. These terms describe the pattern (plain, satin, twill, or basket weave); weight-per-square-yard(in "ounces"); the density of the weave, or "count" (referred to as the "pics-per-inch"); and type of fiber or material used in the weave in each direction(ie: Uni-carbon, using 100% of 3-k carbon fibers in the length direction called the "warp", and S-glass fiberglass in the across direction which is called the "fill"). FABRIC is sold by the square yard or meter, or by the LINEAR YARD... which is how we price here on this website. We have determined it is easier for our customers to simply multiply the price-per-linear-yard x how many yards they want to buy. That means, if you are buying 20 yards, then simply multiply 20 x $/per/linear/yd. As an example: Lets assume the fabric you want to buy costs $10.-/yd., and you want to buy 20 yds., then you would multiply $10.- x 20 yds = $200.- total price. Just call if you need help!

Fiber: Carbon comes from the producer in the form of a "FIBER". Fibers are rated in size with a "K" designation: The "K" of a fiber is how many THOUSANDS of tiny "filaments" are grouped together. The smallest, (and most expensive $ per-pound!) is a "1-K" fiber. The "3-K" size is a more commonly used fiber, it contains 3,000 filaments, or 3-times as many as that in a 1-K fiber. Next up in size/strength, with even higher volume of commercial use, is a "6-K" fiber; then "12-K" etc. Carbon fibers are bought and sold priced "by-the-pound" prior to weaving.

Fill: The across or short direction of the fabric is called the FILL. These fibers will only be as long as the width of the fabric, typically somewhere between 25" to 60" for fabrics, and 1" to 16" for tapes. It is customary to list the FILL specs after the Warp.

Pics: This term tells you how close together the fibers are woven into the fabric. The measurement for this is "PICS"(sometimes spelled PICKS or PIKS), and it is customary to specify how many pics in each direction. How many "pics-per-inch" tells you how many of the carbon fibers are inserted into the weave in each linear inch of fabric. An example of this is a style of weave which has a count of 12 x 8 pics: This means there are 12 fibers per-inch in the WARP, and 8 fibers per-inch in the FILL.

Uni-Directional: The weave of this group of fabrics is usually tailored for a specific set of specifications to meet certain exacting criteria. The criteria may stipulate higher mechanical specifications in WARP, or increased flex in the FILL direction. Uni-Carbon: Its warp has flat non-twisted fibers edge-glued to the side of each other, with NO fibers in the fill...the slight amount of adhesive used holds it all together! Sometimes, instead of glue, a pure Uni has fine little fiberglass or polyester threads about every 1/4" in the fill... just enough to hold the weave together (barely!).

Warp: The next term refers to the lengthwise or long direction of the fabric. Fibers running in the WARP direction can be 100’s of yard long, depending on the length of the roll of fabric. When describing a fabric, it is traditional to stipulate the WARP specs first.

Weave: This term is related to the "FABRIC-STYLE"; it means how a group of fibers are woven together. Referring to the WEAVE STYLE, simply means the pattern in which the fibers are arranged into the fabric. A "Plain" WEAVE is a simple over-under construction (this is the type of weave in all style fabrics unless noted otherwise). Some other examples are "Satin", "Twill" and "Basket" weaves.

Glossary A to D:

Arial Weight - The weight of the fabric per square meter or square yard.

Carbon Assay - Percentage of actual carbon content in fiber.

Carbonization - High temperature process used to convert precursor to carbon fiber.

Certification - If "certified" then give Certification Specs.

Composite - A component produced from two or more different materials. Example: fiber and resin

Denier - Textile term for mass per unit length. Denier is the weight in grams per 1000 meters of material.

Denier Count - Width/Across direction fiber count.

Denier Size - The number of grams per 1000 meters.

Density - Mass per unit volume. Typically grams per cm cubed.

Glossary E to J:

Edge Fiber - Type of fiber used in lengthwise stitching.

Edge Style - Lengthwise stitching style of fabric edge.

Elastic Recovery - Ability to return to previous shape/length after being distorted. This is a function of the modulus of the material and the force that is applied.

Electrical Conductance - Electrical conductance in coulombs per unit length. This is the inverse of electrical resistance which is measured in ohms.

Fiber Count - Lengthwise direction fiber count.

Fringe Edge Trim - Length of the fibers outside of the usable fabric area.

Filament/Denier Size - The number of filaments per tow.

Gigapascal - See Gpa.

Gpa - An SI pressure/strength measurement in force per unit area. 1,000,000,000 pascals. See Pascal.

Inter-laminar Shear Strength - Shear strength between layers of composite sheets or plies. Force needed to pull apart two or more layers.

Glossary K to P:

Longitudinal CTE - CTE is Coefficient of Thermal Expansion. This is the measure of how much a material expands in a parallel axis when heated.

Longitudinal Thermal Conductivity - Ability to conduct heat along a parallel axis.

Manufacturer/Source – Company that makes the carbon fiber.

Matrix Composite - Same definition as composite, but specifically intended as fiber and resin based composites.

Megapascal - See Mpa

Microns - A length measurement: one millionth of a meter.

Modulus - The stiffness of a material. A measure of the force needed to stretch or bend material.

Mpa - An SI pressure/strength measurement on force per unit area. 1,000,000 pascals. See Pascal.

MSI - Mass per unit volume. Typically grams per cm cubed.

Oxidation - Mass per unit volume. Typically grams per cm cubed.

Packaging - Mass per unit volume. Typically grams per cm cubed.

Pascal - A pascal is kilogram force per square meter. Typically used for the units of Tensile Strength.

Precursor - Raw material used to manufacture carbon fiber.

Polyacrylonitrile Precursor - An acrylic fiber based carbon fiber precursor. Used to make PAN based carbon fiber.

Glossary Q to Z:

Roll Length - Roll linear length, plus (+) or minus (-) tolerance.

Roll Core - The interior diametric thickness of the cardboard tube.

Style/Pattern - Weave style or pattern of woven fabric or material.

Surface Area M2/G

Sizing Level - Percentage of chemical treatment versus total fiber weight.

Sizing Type - Sizing resin system compatibility name.

Specific Gravitys - Relationship of the density compared to water where water has a Specific Gravity of 1.0.

SI Units ValueMg/m3 - SI (International System) of units as compared to English Units. Mg/m3 is Mega-grams per millimeter cubed or a density measurement in mass per unit volume.

Tensile - Pressure/Strength measurement.

Tensile Modules - Measurement of elastic stiffness.

Tensile Strain - Elongation of fiber at breaking point. Percentage of stretch.

Tensile Strength - Strength of fiber under tension. Force needed to break material.

Thickness - Thickness in inches or millimeters.

Tow - Continuous filaments per fiber bundle (K=1000)

Tracers - Fibers of different types inserted into weave in a specific pattern (Example: Kevlar tracers in a carbon fabric spaced every 2" in the warp direction).

Twist - Number of twists in a tow or strand of material. Typically measured as twists per meter.

Type/Model - Fiber manufacturers product or ID number.

Yield - Measurement of the amount of mass per unit length.