The mechanical behavior of fiber reinforced thermoplastic composites is mainly influenced by fiber length. However, fiber length is strongly reduced during processing. For this reason direct processing techniques are increasingly applied in order to avoid fiber fracture and thus to generate composites with long fibers. This work investigates the influence of fiber length especially on fatigue behavior of thermoplastic composites. The processing influences on fiber length of composites during injection molding compounding are thereby analyzed and quantified. It is thus shown how to directly influence fiber length in the composite.

The reinforcement of materials such as mud and clay by hair, straw and vegetable fibres has been long established in man's history, enabling him to improve his buildings and extend his engineering abilities. With the advent of modern synthetic polymers it was rapidly realised that the addition of fibres, flakes and particulate materials to polymer matrices could improve mechanical properties significantly. Fibres and flakes are the most effective and have enabled several polymers with limited properties to compete with long-established metallic materials, reSUlting in cost, weight and processing economies. This is increasingly apparent in the selection of materials for aerospace and road vehicle applications as well as in a multitude of domestic products. Reinforced plastics, both thermosets and thermoplastics, are used in increasingly harsh environments involving elevated temperatures and aggressive conditions. Fibre reinforcement of thermoplastics dominates, and a pattern of increasing replacement of fibre reinforced thermosets by reinforced thermoplastics is emerging. This trend is encouraged by the development of continuous fibre reinforced grades of the newer high-temperature engineering thermoplastics such as polyether ether ketone. The first part of this book reviews the mechanical properties and theories of short fibre reinforcement. The principal reinforcements are reviewed and a separate chapter is devoted to the uses of natural fibres as reinforcements for thermoplastics. This is an interesting and commercially important area, especially for Third World countries v vi Preface where these fibres are grown but are facing severe competition from synthetic fibres in traditional applications such as ropes and matting.

This multiauthor volume provides a useful summary of current knowledge on the application of fracture mechanics to composite materials. It has been written to fill the gap between the literature on fundamental principles of fracture mechanics and the special publications on the fracture properties of conventional materials, such as metals, polymers and ceramics.The data are represented in the form of about 420 figures (including diagrams, schematics and photographs) and 80 tables. The author index covers more than 500 references, and the subject index more than 1000 key words.

Science and Engineering of Short Fibre Reinforced Polymer Composites, Second Edition, provides the latest information on the 'short fiber reinforced composites' (SFRP) that have found extensive applications in automobiles, business machines, durable consumer items, sporting goods and electrical industries due to their low cost, easy processing and superior mechanical properties over parent polymers. This updated edition presents new developments in this field of research and includes new chapters on electrical conductivity, structural monitoring, functional properties, self-healing, finite element method techniques, multi-scale SFRCs, and both modern computational and process engineering methods. - Reviews the mechanical properties and functions of short fiber reinforced polymer composites (SFRP) - Examines recent developments in the fundamental mechanisms of SFRP's - Assesses major factors affecting mechanical performance, such as stress transfer and strength - Includes new chapters on electrical conductivity, structural monitoring, functional properties, self-healing, finite element method techniques, multi-scale SFRCs, modern computational methods, and process engineering methods