3d Fabrics By Mahmood Azeem

Introduction The manufacturing of multi layer fabrics is the very first step towards the evolution of 3Dwoven performs. In opposite to 2D-woven fabrics the use of 3D-woven fabrics provides important advantages. The production process is less time-consuming and the fabric offers a high-quality surface. By now there is a possibility to adjust textile fabrics already to a certain shape during the weaving process. These fabrics are called 3Dtextiles . Due to its specific properties it is used in sports, marine, defense etc.

Definition of 3D-Fabrics :

• In most general form we can define 3D-

fabrics as “the single fabric system the constituent yarns of which are supposedly dispose in three mutually perpendicular plane relationship”

Classification of Woven Fabrics • 2D fabrics: Normal two dimensional flat

fabrics. • 2.5D fabrics: The fabrics which are in between 2D and 3D ,like pile fabrics. • 2D woven 3D fabrics: The 3D fabrics made by conventional weaving system. • 3D fabrics: The pure 3D fabrics which do not need any additional binding yarns.

Fibres used in 3D-Fabrics • Glass fibre • Carbon fibre • Aramid fibre

Manufacturing of 2D woven 3D fabrics There are four picks one above the other and like a multi

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plane the weft layers are changing their position intermingle, as visible from different threads moving up and down. The figure also demonstrate very straight stands of warp and weft yarns with zero crimps giving higher yarn orientations resulting in higher in-plane strength and modulus, which is an important property of today's most modern high performance performs. The binding threads are of much finer count as compared to the main enforcing-threads, and this techniques is now being used by 3D –fabric manufactures like 3 tex( USA) for their most modern glass performs. The use was thick floor-covering ,Matts etc.

Cross-sectional view of 2D woven 3D fabrics

3D Weave • In 3D weave all the three orthogonal sets of yarns

highly oriented so good tensile properties should be expected from the composites made by this perform. • Three orthogonal sets of yarns are used to weave the fabric (x,y,z) out of which there are two major yarns groups (x,y) and a binding yarns group (z). X yarns are used as the major warp and Y yarns are used as major weft. The z yarns are used as the binding yarns in the fabric. • Very thick fabrics up to 2” have been developed with considerable width. The weight proportion of the binding threads is a very small about 2% of the fabric weight) so tensile properties of the composites are not suffered.

Carbon /Glass Hybrid 100% Carbon Warp with Glass Filling and Z

3D_fabric dimensions � Width (y) - 2 in. to 72 in. � Thickness (z) - < 0.1 in. to 2 in. � Length (x) - continuous ,cut length<1ft to 20ft> � Shapes , plates, sheets, T, I, Π, angles, pockets, tubes, boxes, � Controlled Fiber Distribution � XYZ, 3D Orthogonal Weave, 0/90/Z � Fiber Vol. Fractions > 55% as woven � Tow packing factors > 65% � Uni-directional to XYZ balanced � Straight internal tow – non-crimp

2D v/s 3D Woven composites • The

unidirectional composites undergo extensive delaminating damage. The main method of through thickness reinforcement include 3D weaving in improving the delaminating resistance.3D Woven fabric composites exhibit higher fraction toughness ,which is about four to five times as compared to uni directional

.

• 3D woven composites exhibit better mechanical

properties than the conventionally 2D woven laminates as shown in the graph.

MPa

A.2D woven composites B.2D woven 3D composites C.3D woven 3D composites

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3TEX 3WEAVE™ 3D Weaving Relative to Standard 2D Improves material performance

• – Non-crimp straight fibers = higher strength and stiffness • – Z direction fiber = improved fracture toughness and damage • tolerance • Lowers fabricated component cost • • • •

– Faster resin wet-out = shorter processing times – Thicker/net-shape and higher conformability = labor savings – Better properties = use less material • Improves quality

• – Thicker and/or net-shape = fewer pieces less assembly error • – Automated textile processing = consistent quality

Mechanical Properties • High tensile strength • High compression strength • Compression strength after impact • High stiffness • Elastic • Low weight

Textile Composites • The textile composites are composed of two materials i.e., a

textile Skelton for reinforcement (called performs) and a binding adhesive ( called matrix) material to keep the Skelton integrated into a specific shape. Without retaining a specific shape, the properties of a composite can not be utilized..

• Parts of a composite: • Perform • matrix

The Performs • Performs of two types either comprising short fibres or

continuo’s fibres. These may be produced in three different ways as indicated below.

Short Fibres materials

yarn

Continuous Fibres materials

Fabric

yarn

Fabric

Composite

Composite

Requirements for the perform manufacture • High degree of structural integrity • Controlled distribution of yarn • Proper orientation of the yarns • Preferably uncrimped yarn • Adequate fibre- volume fraction • Well defined shape and dimensions

Classification The composites w.r.t Matrix • With respect to matrix we can classify composite materials as

• Polymer Matrix composites (PMC’s) • Metal Matrix composites (MMC’s) • Ceramic matrix composites (CMC’s)

Examples of Forms made by Integral 3D Weaving

Applications of 3D Performs

Marine

Aircrafts

Defense

Other fields • Civil Engineering • Sports