TX4008 Structural Mechanics of Yarn Syllabus:

TX4008 Structural Mechanics of Yarn Syllabus – Anna University PG Syllabus Regulation 2021

OBJECTIVE

To enable the students to learn about the structure of ideal and real yarn, migration of fibres in the yarn, breakage mechanism of yarn, mechanics of blended yarns and relationship between structure and property of yarns produced by different spinning systems.

UNIT I YARN GEOMETRY

Elements of yarn geometry; helix geometry of yarn; yarn diameter, twist relationship; ideal packing of fibres in yarn; packing coefficient, estimation of packing density and radial packing density of yarn

UNIT II MIGRATION OF FIBRES IN YARN

Twist contraction and retraction; geometry of folded yarns; migration characteristics in continuous filament and spun yarns; effect of various parameters on migration; measurement of fibre migration in yarn; effect of migration on tensile behavior and hairiness of the yarn

UNIT III YARN MECHANICS

Analysis of breakage of yarn; effect of twist on strength and elongation at break of filament yarn; relationship between elongation at break of filament and yarn; prediction of breakage – continuous filament yarn; model – breakage of spun yarn, effect of twist

UNIT IV BLENDED YARN MECHANICS

Blend irregularity; measurement of blending irregularity, effect on fabric properties; concept of elongation balance; effect of properties of constituent fibres and blend composition on behavior of blended yarns

UNIT V STRUCTURE – PROPERTIES RELATIONSHIP

Structure – property relationship of yarns produced from different spinning systems; effect of fibre properties and geometrical configuration of yarn on properties of ring yarn; comparison of ring and compact spun yarn based on structure

TOTAL: 45 PERIODS

OUTCOMES

On completion of this course, student would understand
CO1: Yarn geometry and packing density
CO2: Migration of fibres in yarn CO3: Breaking mechanics of yarn
CO4: Mechanics of blended yarn
CO5: Structure and properties relationship of yarn

REFERENCES

1. Hearle J.W.S., Grosberg P. and Baker S., “Structural Mechanics of fibres, yarns and fabrics”, Wiley Interscience, New York, 1969.
2. Goswami B.C., Martindale J.G. and Scardino F.L., “Textile Yarns: Technology, Structure and Applications”, Wiley Interscience, New York, 1985
3. Hearle J.W.S., Thwaitesand J.J. and Amikrbayhat A., “Mechanics of Flexible Fibre Assemblies”, Maryland, 1980.
4. Postle P., DejongS. and Carnaby G.A., “The Mechanics of Wool Structure”, Ellis Horwood, London, 1988.
5. 3. Grosberg P. and Iype C., “Yarn production: Theoretical aspects”, Textile Institute publication, 1999, ISBN-13: 978 1 87037 203 9.