This book is a detailed introduction to mechanical alloying, offering guidelines on the necessary equipment and facilities needed to carry out the process and giving a fundamental background to the reactions taking place. El-Eskandarany, a leading authority on mechanical alloying, discusses the mechanism of powder consolidations using different powder compaction processes. A new chapter will also be included on thermal, mechanically-induced and electrical discharge-assisted mechanical milling.
Fully updated to cover recent developments in the field, this second edition also introduces new and emerging applications for mechanical alloying, including the fabrication of carbon nanotubes, surface protective coating and hydrogen storage technology. El-Eskandarany discusses the latest research into these applications, and provides engineers and scientists with the information they need to implement these developments. The industrial applications of nanocrystalline and metallic glassy powders are presented.
The book also contains over 200 tables and graphs to illustrate the milling processes and present the properties and characteristics of the resulting materials.
- Guides readers through each step of the mechanical alloying process, covering best practice techniques and offering guidelines on the required equipment
- Tables and graphs are used to explain the stages of the milling processes and provide an understanding of the properties and characteristics of the resulting materials
- A comprehensive update on the previous edition, including new chapters to cover new applications
Life in the current twenty-first century cannot be depending on limited groups of materials, instead it is dependent on unlimited families of advanced materials. Laptop computers, digital cameras, smart cell phones, nanosensors, microwave ovens, computerized cars, bio-microelectromechanics, thin film photovoltaics, and many other intelligent devices and instruments used in many sectors require special type of materials that have superior properties. In spite of the traditional categories of materials (metals and metal alloys, ceramics, polymer, and composites) that do not match well with the whole modern industries' requirements, a newcomer so-called "advanced materials" has found an important space in the functional classifications of the materials. However, the advanced materials can be defined in numerous ways based on their properties and usages, and we can define them as those materials that show advances over the traditional materials and used for manufacturing of high-tech products. Thus, the advanced materials refer to all new materials and developing to the existing materials to obtain superior, unique, and high performance in one or more properties. Amorphous and metallic glasses, nanomaterials and nanocomposites, biomaterials, semiconductors, and smart or so-called intelligent materials are some types of the advanced materials used in different sectors.
Advanced materials; fabrication; mechanical approach; thermal approach; ball milling; thermal plasma processing; vapor deposition
The capability of any societies along the human history on developing and instigating of new materials that fit their needs has led to the advancement of their performance and ranking worldwide. The gap differences on the "level of life," indexed by the progress made on health, education, industry, economic, culture, etc., between a country to country and region to another are always attributed to the man's ability for developing materials and manufacturing equipment and devises used for materials fabrications and characterizations. However, there are many approaches and techniques used for producing the advanced materials; mechanical alloying has been receiving great attentions and considerations as a unique process for synthesizing of new advanced materials families that cannot be obtained by any other techniques. Nanostructured materials, nanoparticles, nanocomposites, carbon nanotubes, amorphous and metallic glassy and alloys are some of those new engineering materials that can be successfully obtained by such a room temperature way of fabrication. The figure shows an image of high resolution transmission electron microscope (HRTEM) for a single wall carbon nanotube (SWCNT) prepared by the author, using a chemical vapor deposition (CVD) equipment housed in the Nanotechnology Laboratory, Energy and Building Research Center (EBRC), Kuwait Institute for Scientific Research (KISR).
1.1 Advanced materials
Life in the current twenty-first century cannot be depending on limited groups of materials, instead it is dependent on unlimited families of advanced materials. Laptop computers, digital cameras, smart cell phones, nanosensors, microwave ovens, computerized cars, bio-microelectromechanics, thin film photovoltaics, and many other intelligent devices and instruments used in many sectors require special type of materials that have superior properties. In spite of the traditional categories of materials (metals and metal alloys, ceramics, polymer, and composites) that do not match well with the whole modern industries' requirements, a newcomer so-called "advanced materials" has found an important space in the functional classifications of the materials. However, the advanced materials can be defined in numerous ways based on their properties and usages, and we can define them as those materials that show advances over the traditional materials and used for manufacturing of high-tech products. Thus, the advanced materials refer to all new materials and their development to the existing materials to obtain superior, unique, and high performance in one or more properties. Amorphous and metallic glasses, nanomaterials and nanocomposites, biomaterials, semiconductors, and smart or so-called intelligent materials are some types of the advanced materials used in different sectors (Figure 1.1). Figure 1.1
Advanced materials, such as metallic glasses, nanomaterials, biomaterials, smart materials, nanocomposites, semiconductors, etc., that are used in different industrial, medical, electronic, and many other sectors are prepared by wide variety of materials processing.
1.2 Strategies used for fabrication of advanced materials
Although, there are numerous standard fabrication methods that have been used for producing and fabrication of the traditional materials, including hydrometallurgy, pyrometallurgy, and powder metallurgy (P/M), the advanced materials cannot be prepared easily by any of them. Within the last six decades, materials scientists have developed several synthesizing approaches and methods used for synthesizing of new families of materials so-called advanced or "high-tech" materials that show unusual and superior chemical, physical, and mechanical properties.
These new routes of material processing and fabrication have led to control the materials' subatomic structure and tailoring the materials with desired and predetermined structure. Tailoring the materials structure by controlling their atomic arrangements (e.g., long-range order or short-range order) affects the whole properties of materials to attain high performance characterizations. Moreover, controlling the morphological and microscopic (shape and size) characterizations of the materials leads to significant changes in their properties and behaviors. It can be concluded that the way in which a material is produced (materials processing and fabrications) affects the atomic arrangements and microscopic properties of it and this will not only lead to develop the whole properties of the product but it also affects its performance and future applications, as schematically presented in Figure 1.2, which shows the interrelationship between preparations and processing, structure, properties, and performance. Figure 1.2
Schematic presentation of processing/structure/properties/performance interrelationship of advanced materials.
The recent investigations made by the materials scientists within the last few decades enable us to prepare wide types of advanced materials through new approaches of preparations. In general, the strategies used for fabrication of the advanced materials may be classified as: (i) mechanically assisted approach, (ii) mechanically induced solid-state reaction approach, (iii) thermally assisted approach, (iv) high energy-assisted approach, (v) chemically assisted approach, (vi) lithographic approach, (vii) vapor deposition approach, and (viii) liquid-phase fabrication approach.
Some examples of new materials preparation methods, such as ball milling, rapid solidification (RS), atomization, sputtering, chemical vapor deposition (CVD), electron beam physical vapor deposition (EBPVD), arc discharge, laser ablation (LA), photolithography, nano-imprint lithography, sol-gel, atomic force microscope, nanostencil, plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), and atomic layer deposition (ALD), which have been used for producing wide varieties of advanced materials are illustrated in Figure 1.1.
1.3 Mechanically assisted approach
1.3.1 Powder metallurgy
Powder metallurgy (P/M) can be simply defined as the cost-effective process of manufacturing of components and tools starting from metallic, ceramic, or composite powders. In fact, P/M is not a new process in our world of materials science; it dates back to 3,000 BC, when the Egyptian employed it for preparing iron powder from "sponge iron" to make their tools . At that time, high-temperature furnaces were not available yet. Since then, P/M has been considered as a practical process that can be successfully used for net-shaped or near-net-shaped formation of high-melting point metals, metal oxides, and cemented carbides without any need of melting and casting processes. The development of this process has led today to produce high-quality iron powder by grinding and then ball milling of the sponge iron into fine particles and followed by heating the as-milled iron powders in hydrogen to remove the oxides. Modern P/M technology was started in the second decade of the last century with a glorious achievement at that time, when a mass production of qualified tungsten carbide powders could be produced in industrial scale. During the period of time, between 1920s and 1940s, the worldwide interest in P/M technology was monotonically increased, especially after the mass production of porous bronze brushes for bearings in 1920s . During the World War II and till 1960s, wide varieties of new composites, ferrous- and nonferrous-based materials, were developed. Within the last 50 years, glorious progress in the area of powder consolidation has been achieved, and new powder pressing techniques, such as cold/hot isostatic pressing, spark plasma sintering, shock-wave consolidation, induction hot pressing, etc., have been introduced. Accordingly, P/M has drastically grown due to its capability of producing large-scale volume of powders and consolidated precision and complex near-net-shaped dense components. Figure 1.3...