1.

Record Nr.

UNINA9910476876403321

Autore

Trauth Anna

Titolo

Characterisation and Modelling of Continuous-Discontinuous Sheet Moulding Compound Composites for Structural Applications / / Anna Trauth

Pubbl/distr/stampa

Karlsruhe : , : KIT Scientific Publishing, , 2020

Descrizione fisica

1 online resource (468 pages) : illustrations

Collana

Schriftenreihe des Instituts für Angewandte Materialien, Karlsruher Institut für Technologie

Disciplina

731.42

Soggetti

Modeling

Mechanical engineering

Lingua di pubblicazione

Inglese

Formato

Materiale a stampa

Livello bibliografico

Monografia

Nota di contenuto

List of Figures  xv -- List of Tables xxiii -- List of Abbreviations and Symbols  xxv -- 1 Introduction. 1 -- 1.1 Motivation . 1 -- 1.2 Scope and objective. 5 -- 1.3 Contribution to the current state of research. 6 -- 1.4 Outline of this dissertation  8 -- 2 Current state of research  9 -- 2.1 Definition of hybrid materials  9 -- 2.2 Composite materials . 14 -- 2.2.1 Definition and fundamentals  14 -- 2.2.2 Basic mechanisms of fibrous reinforcement. 16 -- 2.3 Sheet moulding compound composites. 21 -- 2.3.1 Definition and terminology delimitation  21 -- 2.3.2 Discontinuous SMC composites  21 -- 2.3.3 Continuous SMC composites 57 -- 2.4 Hybrid composites . 61 -- 2.4.1 Definition, motivation and development -- of hybrid composites . 62 -- 2.4.2 Evaluation of hybridisation effects . 65 -- 2.4.3 Existing concepts of hybrid SMC . 68 -- 2.5 Research questions . 82 -- 3 Materials and specimen geometries  85 -- 3.1 Manufacturing of SMC composites  85 -- 3.1.1 Composition of resin systems . 85 -- 3.1.2 Manufacturing of semi-finished sheets  87 -- 3.1.3 Manufacturing of compression moulded sheets . 89 -- 3.1.4 Manufacturing of pure resin sheets  92 -- 3.1.5 Manufacturing of demonstrator part  93 -- 3.2 Specimen preparation and geometry 94 -- 3.2.1 Water-jet cutting and milling  94 -- 3.2.2 End tabs. 95 -- 3.2.3 Specimen geometries . 95 -- 4 Experimental setups, procedures and data evaluation  103 -- 4.1



Characterisation strategy  103 -- 4.2 Characterisation at the coupon level  105 -- 4.2.1 Microstructural characterisation  105 -- 4.2.2 Macrostructural characterisation . 106 -- 4.3 Characterisation at the structure level. 114 -- 4.3.1 Quasi-static puncture testing  114 -- 4.3.2 Dynamic puncture testing . 116 -- 4.4 Characterisation at the component level  118 -- 4.5 Data evaluation . 121 -- 5 Analytical modelling  123 -- 5.1 Description of modelling approach 123 -- 5.2 Micromechanics and homogenisation methods . 124 -- 5.2.1 Fundamentals of homogenisation  124 -- 5.2.2 Analytical modelling of fibre reinforced polymers 128 -- 5.3 Classical laminate theory  133 -- 5.3.1 Macromechanical characterisation of a lamina . 134 -- 5.3.2 Macromechanical characterisation of a laminate. 134 -- 5.4 Analytical modelling of hybrid composites  138 -- 5.4.1 Rule of hybrid mixtures  139 -- 5.4.2 Tensile and flexural modulus based on classical laminate theory . 140 -- 6 Results . 143 -- 6.1 Evaluation of testing methods and preliminary studies . 143 -- 6.1.1 Tensile properties of discontinuous SMC composites . 144 -- 6.1.2 Tensile properties of continuous SMC composites 150 -- 6.1.3 Flexural properties of SMC composites . 152 -- 6.2 Microstructural analysis . 158 -- 6.2.1 Fibre volume content . 158 -- 6.2.2 Fibre orientation distribution 164 -- 6.2.3 Interface of continuous-discontinuous SMC  173 -- 6.3 Mechanical properties and failure at the coupon level . 176 -- 6.3.1 Tensile and compressive properties of -- polyester-polyurethane hybrid resin . 176 -- 6.3.2 Process-induced material properties of -- discontinuous glass fibre SMC  179 -- 6.3.3 In-plane loading of SMC composites  190 -- 6.3.4 Out-of-plane loading of SMC composites . 229 -- 6.4 Mechanical properties and failure at the structure level . 237 -- 6.4.1 Puncture properties of discontinuous glass fibre SMC  238 -- 6.4.2 Puncture properties of continuous carbon fibre SMC . 248 -- 6.4.3 Puncture properties of continuous-discontinuous glass/carbon fibre SMC  256 -- 6.5 Mechanical properties and failure at the component level . 268 -- 6.6 Analytical stiffness prediction  271 -- 6.6.1 Analytical stiffness prediction of discontinuous glass fibre SMC  272 -- 6.6.2 Analytical stiffness prediction of continuous carbon fibre SMC . 277 -- 6.6.3 Analytical stiffness prediction of continuous-discontinuous glass/carbon fibre SMC  279 -- 7 Discussion. 283 -- 7.1 Testing methodology and preliminary studies  283 -- 7.2 Material behaviour of unsaturated polyester-polyurethane two-step curing hybrid resin system 285 -- 7.3 Discontinuous glass fibre SMC . 287 -- 7.3.1 Microstructural aspects of discontinuous glass fibre SMC  287 -- 7.3.2 Mechanical behaviour and damage evolution of discontinuous glass fibre SMC . 291 -- 7.4 Continuous carbon fibre SMC  301 -- 7.4.1 Microstructural aspects of continuous carbon fibre SMC . 301 -- 7.4.2 Mechanical behaviour and damage evolution of continuous carbon fibre SMC  302 -- 7.5 Continuous-discontinuous glass/carbon fibre SMC  308 -- 7.5.1 Microstructural aspects of continuous-discontinuous glass/carbon fibre SMC  308 -- 7.5.2 Mechanical properties, damage evolution and hybridisation effect  310 -- 8 Final remarks . 347 -- 8.1 Summary . 347 -- 8.2 Conclusion . 356 -- Bibliography 361 -- A Appendix  403 -- A.1 Influence of subset size and step size . 403 -- A.2 Influence of edge preparation  405 -- A.3 Tensile properties of discontinuous glass fibre SMC (2D) . 406 -- A.4 Tensile properties of discontinuous glass fibre SMC (1D) . 407 -- A.5 Compressive properties of discontinuous glass fibre SMC . 408 -- A.6 Tensile and compressive properties of continuous carbon fibre SMC . 409 -- A.7 Flexural properties of continuous carbon fibre SMC. 410 -- A.8 Flexural properties of continuous-discontinuous glass/carbon fibre SMC . 411 -- A.9 Classical laminate theory: calculations 412.



Sommario/riassunto

The main objective of this work is to significantly deepen the understanding of the material and the structural behaviour of continuous-discontinuous SMC composites, following a holistic approach to investigate microscopic aspects, macroscopic mechanical behaviour as well as failure evolution at the coupon, structure and component level. In addition, criteria to evaluate the effect of hybridisation are introduced and modelling approaches are presented and discussed.