Composite Sheet Forming

by Bhattacharyya, D.

• ISBN13: 9780444826411
• ISBN10: 0444826416
• Format: Hardcover
• Copyright: 1997-06-01
• Publisher: Elsevier Science Ltd

Summary

Sheet forming is the most common process used in metal forming and is therefore constantly being adapted or modified to suit the needs of forming composite sheets. Due to the increasing availability of various types of fibre reinforced polymeric sheets, especially with thermoplastic matrices, the scope of use of such materials is rapidly expanding in the automobile, building, sports and other manufacturing industries beyond the traditional areas of aerospace and aircraft applications. This book contains twelve chapters and attempts to cover different aspects of sheet forming including both thermoplastic and thermosetting materials. In view of the expanded role of fibre reinforced composite sheets in the industry, the book also describes some non-traditional applications, processes and analytical techniques involving such materials.

The first chapter is a brief introduction to the principles of sheet metal forming. The next two chapters introduce the various forms of materials, manufacturing techniques and the fundamentals of computer simulation. Chapter 4 describes the different aspects of thermoforming of continuous fibre reinforced thermoplastics and the following chapter studies the shear and frictional behaviour of composite sheets during forming. Chapter 6 explores the possibility of applying the grid strain analysis method in continuous fibre reinforced polymeric sheets. The next two chapters address fundamental concepts and recent developments in finite element modelling and rheology. Chapter 9 introduces the theory of bending of thermoplastic composite sheets and shows a novel way of determining both longitudinal and transverse viscosities through vee-bend tests. A significant expansion in the usage of composite materials is taking place in biomedical areas. Chapter 10 discusses the thermoforming of knitted fabric reinforced thermoplastics for load bearing and anisotropic bio-implants. The final chapter introduces roll forming, a commonly used rapid manufacturing process for sheet metals, and discusses the possibility of applying it economically for continuous reinforced thermoplastic sheets.

Table of Contents

Preface	v	(2)
List of Contributors	vii
J. L. Duncan
S. M. Panton
Chapter 1 Introduction to sheet metal forming	1	(26)
Abstract	1	(1)
1.1. Introduction	2	(1)
1.2. Introduction to plastic flow theory	2	(4)
1.3. Forming characteristics of sheet metals	6	(6)
1.4. Forming limits for sheet metal	12	(3)
1.5. Industrial sheet metal forming	15	(4)
1.6. Bending and spring-back	19	(4)
1.7. Superplasticity	23	(2)
References	25	(2)
B. Tomas Astrom
Chapter 2 Thermoplastic composite sheet forming: materials and manufacturing techniques	27	(48)
Abstract	27	(1)
2.1. Introduction	28	(1)
2.2. Constituents	29	(19)
2.3. Properties	48	(12)
2.4. Manufacturing techniques	60	(12)
Acknowledgement	72	(1)
References	72	(3)
B. L. Koziey
M. O. Ghafur
J. Vlachopoulos
F. A. Mirza
Chapter 3 Computer simulation of thermoforming	75	(16)
Abstract	75	(1)
3.1. Introduction	76	(1)
3.2. Sheet production	77	(1)
3.3. Thermoforming simulation	78	(10)
3.4. Concluding remarks	88	(1)
References	88	(3)
K. Friedrich
M. Hou
J. Krebs
Chapter 4 Thermoforming of continuous fibre/thermoplastic composite sheets	91	(72)
Abstract	92	(1)
4.1. Introduction	92	(4)
4.2. Experimental details and procedures	96	(4)
4.3. 2-D stamp forming	100	(37)
4.4. 3-D stamp forming	137	(9)
4.5. 3-D diaphragm forming of GF/PP laminates	146	(13)
4.6. Summary	159	(1)
Acknowledgements	160	(1)
References	160	(3)
A. M. Murtagh
P. J. Mallon
Chapter 5 Characterisation of shearing and frictional behaviour during sheet forming	163	(54)
Abstract	163	(1)
5.1. Introduction	164	(6)
5.2. Transverse fibre flow	170	(3)
5.3. Intra-ply shear	173	(4)
5.4. Inter-ply slip	177	(20)
5.5. Friction during thermoforming	197	(17)
References	214	(3)
T. A. Martin
G. R. Christie
D. Bhattacharyya
Chapter 6 Grid strain analysis and its application in composite sheet forming	217	(30)
Abstract	217	(1)
6.1. Introduction	218	(1)
6.2. Large strain analysis	218	(6)
6.3. Method of least squares fitting	224	(2)
6.4. Forming a composite spherical dome	226	(4)
6.5. Forming a composite blister fairing	230	(4)
6.6. Draping theory of textile fabrics	234	(4)
6.7. Diagnostic applications	238	(3)
6.8. Concluding remarks	241	(3)
References	244	(3)
C. M. O Bradaigh
G. B. McGuinness
S. P. McEntee
Chapter 7 Implicit finite element modelling of composites sheet forming processes	247	(76)
Abstract	248	(1)
7.1. Introduction	248	(6)
7.2. Modelling of composite sheets during forming	254	(4)
7.3. Numerical solutions -- plane stress problems	258	(5)
7.4. Central indentation of a composite sheet -- the shear-buckling problem	263	(23)
7.5. Experimental comparisons -- diaphragm forming	286	(17)
7.6. Conclusions of plane stress analysis	303	(2)
7.7. Numerical solutions -- plane deformation problems	305	(10)
7.8. Conclusions of plane deformation analysis	315	(3)
Acknowledgements	318	(1)
Nomenclature	318	(1)
References	319	(4)
S. G. Advani
T. S. Creasy
S. F. Shuler
Chapter 8 Rheology of long fiber-reinforced composites in sheet forming	323	(48)
Abstract	324	(1)
8.1. Introduction	324	(5)
8.2. Rheological properties	329	(19)
8.3. Rheological measurement techniques	348	(8)
8.4. Why the rheological properties are important and how to use them in sheet forming	356	(10)
8.5. Outlook	366	(1)
References	367	(4)
T. A. Martin
S. J. Mander
R. J. Dykes
D. Bhattacharyya
Chapter 9 Bending of continuous fibre-reinforced thermoplastic sheets	371	(32)
Abstract	371	(1)
9.1. Introduction	372	(2)
9.2. Development of an idealised viscous bending model	374	(6)
9.3. Experimental procedures	380	(2)
9.4. Results and discussion	382	(10)
9.5. Modified constant shear rate tests	392	(7)
9.6. Conclusions	399	(1)
Acknowledgements	399	(1)
References	400	(3)
J. Mayer
E. Wintermantel
Chapter 10 Thermoforming processes for knitted-fabric-reinforced thermoplastics: new manufacturing techniques for load-bearing, anisotropic implants	403	(38)
Abstract	404	(1)
10.1. General aspects of anisotropic biomaterials for load-bearing implants	404	(1)
10.2. Knitted-carbon-fiber-reinforced composite materials	405	(14)
10.3. Net-shape forming of knitted fabrics for load-transmitting implants shown for an ulnar osteosynthesis plate	419	(9)
10.4. Deep drawing of knitted-fiber-reinforced organo-sheets	428	(4)
10.5. Discussion	432	(3)
10.6. Summary and conclusions	435	(1)
Acknowledgements	435	(1)
References	436	(5)
H. Li
T. Gutowski
Chapter 11 The forming of thermoset composites	441	(32)
Abstract	441	(1)
11.1. Introduction to thermoset forming	442	(4)
11.2. Kinematics	446	(9)
11.3. Thermoset forming experiments and forming limit analysis	455	(13)
11.4. Concluding remarks	468	(3)
References	471	(2)
S. J. Mander
S. M. Panton
R. J. Dykes
D. Bhattacharyya
Chapter 12 Roll forming of sheet materials	473	(44)
Abstract	474	(1)
12.1. Introduction	474	(2)
12.2. Roll forming equipment and tooling	476	(7)
12.3. Conventional form roll design	483	(6)
12.4. Computer-aided design in roll forming	489	(2)
12.5. Deformation analysis of roll forming	491	(7)
12.6. Roll forming of thermoplastic material	498	(14)
12.7. Concluding remarks	512	(1)
Acknowledgements	513	(1)
References	513	(4)
Author Index	517	(8)
Subject Index	525