The use of natural fibres as replacement for traditional glass fibers in composites has gained increasing importance in recent years as environmental concerns have led to a quest for sustainable alternatives. However natural fibre composites have generally been found to have limitations in their mechanical properties. This book presents the results of studies undertaken to explore the mechanical properties, especially impact and fatigue, of hemp fibre reinforced polyester composites. The specific tensile properties and impact damage tolerance of hemp fibre composites were found to be low compared to glass fibre composites. Despite having poorer absolute fatigue strength, hemp fibre composites exhibited better fatigue sensitivity than glass fibre composites in tension-tension fatigue. The effects of water immersion and various fibre surface treatments on the impact and fatigue properties of hemp fibre composites were also studied.
The manual is intended for the 5th year students of the Polymer Faculty of 020015 «Chemical Technology» course. The manual reflects the current state of the elastomers science and production technologies. The focus is on technological methods, based on the scientific understanding of the chemistry in the synthesis of general-purpose and special rubbers, their properties and applications.The content of the manual corresponds to the program of the course «Technology of Elastomers». Published by the decision of the Editing and Publishing Board of Kazan National Research Technological University
Polymer blends are gaining technological importance due to their compromise set of properties, advantages in processing and reduction in cost. One polymer may possess a particular set of properties, while the other may have another set of properties. By blending two such polymers, a desired set of properties can be achieved. In the case of elastomers, blends are used in tires, belts, cables etc. For the successful applications of such blends, component elastomers must be miscible and compatible. The curing method adopted and the distribution of compounding ingredients has a vital role on the ultimate properties. The distribution depends mainly on the nature of the elastomers and the blending process. Therefore, knowledge of these parameters will facilitate in obtaining a successful elastomer blend. In the present work, investigation has been carried out on the compatibility and mechanical properties of blends consisting of ethylene propylene diene rubber (EPDM) and chlorobutyl rubber (CIIR). This blend finds application in the manufacture of curing envelope and other high temperature performances.
Many sliding machines are subject to high-temperature environments. Solid lubricating coatings are primarily used to control friction and wear in high temperature environments, where conventional liquid lubricants cannot provide lubrication function due to deterioration and oxidation at high temperature. Among solid lubricating coatings, carbonaceous coatings attract much attention because of their excellent mechanical propertiesand tribological properties, such as low friction, high hardness and high wear resistance. However, the high temperature tribolgical behaviors and mechanism of carbonaceous are still not clarified yet up to now. Consequently, in this study, a-C:H, Si-DLC, CNx, BCN, ta-C coatings were prepared and their thermal stability and high temperature tribological properties were investigated.
We are surrounded by polymers: Whether it's to prepare a meal, use computer keyboards and mousepads, or step onto a new playground, you'll encounter a plastic product made of polymers. Owing to the extraordinary range of properties accessible in polymeric materials, they play an essential and ubiquitous role in everyday life – from plastics and elastomers on the one hand to natural biopolymers such as DNA and proteins that are essential for life on the other. This desktop and library reference book provides a comprehensive yet concise overview of the materials, manufacture, structure and architecture, properties, processing, and applications of withing the field of polymers. The book offers a unique mix of theory and application, the essential personal reference for anyone studying or working within the field of polymers.
Fatigue resistance in filled rubbers is largely dependent on the energy available to propagate a crack, but the influence of the stress concentration is undetermined in elastomeric fatigue. In metals fatigue,a stress concentration is virtually unaltered by cyclic loading. Rubber undergoes large reversible strains and it is argued that rubber components have less severe surface flaws when preloaded than in a stress free state. In fatigue, higher stress levels in the pre-stressed (pre-strained) material are thought to be partially compensated for by improvements in surface finish. It is expected that the size of flaws introduced during the manufacturing process, irrespective of whether the part is made by compression, injection or transfer moulding, can induce early failure of the specimen when it is under load. The fundamental question posed is ‘can surface treatments influence fatigue resistance?'' Reducing the size of a flaw has the potential to reduce concentration under load and thereby improve resistance. This book describes an investigation of the influence of surface treatments and surface finish on the fatigue properties of EPDM and Natural Rubbers.
A comprehensive and up-to-date overview of the major mineral and organic fillers for plastics, their production, structure and properties, as well as their applications in terms of primary and secondary functions. Edited and co-authored by Professor Marino Xanthos with contributions by international experts from industry and academia, this book presents methods of mixing/incorporation technologies, surface treatments and modifications for enhanced functionality, an analysis of parameters affecting filler performance and a presentation of current and emerging applications. Additionally, the novel classification according to modification of specific polymer properties rather than filler chemical composition provides a better understanding of the relationships between processing, structure and properties of products containing functional fillers and the identification of new markets and applications. For engineers, scientists and technologists involved in the important sector of polymer composites.
The design of mechanical structures with improved and predictable durability cannot be achieved without a thorough understanding of the mechanisms of fatigue damage and more specifically the relationships between the microstructure of materials and their fatigue properties. Written by leading experts in the field, this book (which is complementary to Fatigue of Materials and Structures: Application to Damage and Design, also edited by Claude Bathias and André Pineau), provides an authoritative, comprehensive and unified treatment of the mechanics and micromechanisms of fatigue in metals, polymers and composites. Each chapter is devoted to one of the major classes of materials or to different types of fatigue damage, thereby providing overall coverage of the field. The book deals with crack initiation, crack growth, low-cycle fatigue, gigacycle fatigue, shorts cracks, fatigue micromechanisms and the local approach to fatigue damage, corrosion fatigue, environmental effects and variable amplitude loadings, and will be an important and much used reference for students, practicing engineers and researchers studying fracture and fatigue in numerous areas of mechanical, structural, civil, design, nuclear, and aerospace engineering as well as materials science.
The design of mechanical structures with predictable and improved durability cannot be achieved without a thorough understanding of the mechanisms of fatigue damage and more specifically the relationships between the microstructure of materials and their fatigue properties. Written by leading researchers in the field, this book, along with the complementary books Fatigue of Materials and Structures: Fundamentals and Application to Damage and Design (both also edited by Claude Bathias and André Pineau), provides an authoritative, comprehensive and unified treatment of the mechanics and micromechanisms of fatigue in metals, polymers and composites. Each chapter is devoted to one of the major classes of materials or to different types of fatigue damage, thereby providing overall coverage of the field. This book deals with multiaxial fatigue, thermomechanical fatigue, fretting-fatigue, influence of defects on fatigue life, cumulative damage and damage tolerance, and will be an important and much used reference for students, practicing engineers and researchers studying fracture and fatigue in numerous areas of materials science and engineering, mechanical, nuclear and aerospace engineering.
CONTENTS - INTRODUCTION - CHAPTER I. SINGLE CRYSTALS: THEIR GROWTH METHODS AND MECHANICAL PROPERTIES - 1. Methods of growing single crystals - 2. Mechanical propertIes of metal sIngle crystals - 3. RelatIon between the mechanical properties of single crystals, and temperature and deformation rate - CHAPTER II. RULES GOVERNING THE DEFORMATION OF METAL SINGLE CRYSTALS IN THE PRESENCE OF SURFACE ACTIVE SUBSTANCES - 1. Experimental method - 2. Principal regularities - 3. Influence of temperature and deformation rate on the value of the adsorptlon effect - 4. Effect of stress on the value of the adsorption effect - 5. Adsorption effect in the initial plastic region in the deformation of single crystals - CHAPTER III. CREEP OF SINGLE CRYSTALS - ELECTROCAPILLARY EFFECT - 1. Creep of sIngle crystals - 2. The electrocapillary effect - CHAPTER IV. EFFECT OF SURFACE ACTIVE MEDIA ON THE MECHANICAL PROPERTIES OF POLYCRYSTALLINE METALS - 1. Effect on the elastic deformations - 2. Effect of the medium on plastIc flow and creep of metals - 3. Increased hardening of metals under the effect of surface actIve media during cyclic deformations - 4. Adsorption effect during alternating torsion and the problem of metal fatigue - CHAPTER V. METAL FATIGUE - CORROSION AND ADSORPTION FATIGUE - 1. General - 2. Experimental method - CHAPTER VI. PRINCIPAL MECHANISMS GOVERNING THE ADSORPTION FATIGUE OF METALS - 1. Effect of cooling action by liquid media on the fatigue strength of steels - 2. Adsorption an...
The Basics of Troubleshooting in Plastics Processing is a condensed practical guide that gives the reader a broad introduction to properties of thermoplastics plastics, additives, the major processes (extrusion, injection molding, rotational molding, blow molding, and thermoforming), as well as troubleshooting. The main goal is to provide the plastics processor with an improved understanding of the basics by explaining the science behind the technology. Machine details are minimized as the emphasis is on processing problems and the defects in an effort to focus on basic root causes to problems and how to solve them. The book’s framework is troubleshooting in plastics processing because of the importance it has to the eventual production of high quality end products. Each chapter contains both practical and detailed technical information. This basic guide provides state-of-the-art information on: Processing problems and defects during manufacturing Plastics materials, their properties and characterization The plastics processing techniques Plastics additives Troubleshooting of the 5 main plastics processes References for further reading
In the present research work effort has been made to study the tribological behavior of dual particle size (DPS) and triple particle size (TPS) of Al2O3 reinforced Al-MMCs (prepared by vacuum moulding process). The study started with selection of the component for industrial application. The study highlights the effect of reinforcement in form of DPS and TPS on mechanical and metallurgical properties of Al- Al2O3 MMCs. The input parameters of process are composition of MMC, vacuum moulding silica sand grain size, vacuum pressure and component volume. The study highlights the percentage contribution of different input parameters on micro hardness, dimensional accuracy and wear properties of Al- Al2O3 MMCs.
This is the first detailed description in English of radiation and polymeric material interaction and the influences of thermal and optical material properties. As such, it provides comprehensive information on material and process characteristics as well as applications regarding plastic laser welding. The first part of this practical book introduces the structure and physical properties of plastics, before discussing the interaction of material and radiation in the NIR and IR spectral range. This is followed by an overview of the physical foundations of laser radiation and laser sources used for plastic welding. The third part describes the main processes of laser welding thermoplastics, as well as possibilities of process control, design of joint geometry, material compatibilities and adaptation of absorption of plastics to NIR radiation. Finally, the author explains applications of laser welding plastics using several industrial case studies from the automotive industry, household goods, and medical devices. Tailored to the needs of everyone dealing with laser welding of plastics, especially engineers in packaging, component manufacturing, and the medical industry.
Conductive polymers are organic compounds that conduct electricity. Such compounds may be true metallic conductors or semiconductors. It is generally accepted that metals conduct electricity well and that organic compounds are insulating, but this class of materials combines the properties of both. The biggest advantage of conductive polymers is their processibility. Conductive polymers are also plastics (which are organic polymers) and therefore can combine the mechanical properties (flexibility, toughness, malleability, elasticity, etc.) of plastics with high electrical conductivities. Their properties can be fine-tuned using the exquisite methods of organic synthesis. Different additives are usually added to polymer in order to modify and improve its properties. Inorganic additives such as transition metal salts have considerable effect on the optical and electrical properties of polymers.
Duplex Stainless Steels (DSSs) are chromium-nickel-molybdenum-iron alloys that are usually in proportions optimized for equalizing the volume fractions of austenite and ferrite. Due to their ferritic-austenitic microstructure, they possess a higher mechanical strength and a better corrosion resistance than standard austenitic steels. This type of steel is now increasing its application and market field due to its very good properties and relatively low cost. This book is a review of the most recent progress achieved in the last 10 years on microstructure, corrosion resistance and mechanical strength properties, as well as applications, due to the development of new grades. Special attention will be given to fatigue and fracture behavior and to proposed models to account for mechanical behavior. Each subject will be developed in chapters written by experts recognized around the international industrial and scientific communities. The use of duplex stainless steels has grown rapidly in the last 10 years, particularly in the oil and gas industry, chemical tankers, pulp and paper as well as the chemical industry. In all these examples, topics like welding, corrosion resistance and mechanical strength properties (mainly in the fatigue domain) are crucial. Therefore, the update of welding and corrosion properties and the introduction of topics like texture effects, fatigue and fracture strength properties, and mechanical behavior modeling give this book specific focus and character.