The Technology of Materials

This introductory chapter discusses atoms and bonds—the basics of the inorganic chemistry of materials—and also sketch out the ways of dealing with these building blocks in different disciplines. Materials chemistry is not a sharply bounded and institutionalized subject but a combination of many crafts and sciences. Some awareness of the norms in relevant areas is necessary for materials designers, who must get their information from those fields. 

It is clear, then, that some knowledge of the chemistry of the elements is a prerequisite for being able to use them. Societal demands for alternative resources, dematerialization, and durability are also compelling reasons for achieving a thorough knowledge of the chemical behavior of matter  

Alternatives are cheap, easily processed, and abundantly available replacements for expensive, scarce, and strategic elements, e.g., cobalt and chromium, necessary in 

There is one basic question in materials chemistry how to make what we want Synthesis is the central issue addressed in this book. Several questions arise  

The playing field for this game is the periodic table. What are the properties of the elements This question covers the entire field of inorganic chemis-try 3.4 applicable elements and their behaviors are selected here. Key periodicities in the periodic table are noted in the next section, and they are basic for the use of the elements in compounds. Consideration of the properties of the elements is inherent in all the individual subjects dealt with in this volume. 

---

In conclusion, we would like to mention that, in addition to this new direction, a large consumer of metal alkoxides (initially aluminium and titanium) is by tradition the technology of materials, where the alkoxides are used for hy-drophobization and for cross-linking of the polyhydroxocompounds, epoxides and polyester resins, and organosilicon polymers. The products of the partial hydrolysis and pyrolysis of alkoxides — polyorganometalloxanes — are applied as components of the thermally stable coatings [48J. 

These parameters stimulated the development of functional products using the advances that had accrued in the technology of materials. This development was closely followed by products derived from the advances in the development of synthetic polymers. A statement of required performance could now be considered a possible specification for a polymeric product. 

Recent advances in material sciences have been the cause and effect of advances in the technology of materials characterization. 

Reactions between solids are of considerable importance in the technology of materials processing. For the purpose of classification these reaction systems may be divided into the following two main groups ... 

Researches when working out the technology of constructional materials... 

The Institute has many-year experience of investigations and developments in the field of NDT. These are, mainly, developments which allowed creation of a series of eddy current flaw detectors for various applications. The Institute has traditionally studied the physico-mechanical properties of materials, their stressed-strained state, fracture mechanics and developed on this basis the procedures and instruments which measure the properties and predict the behaviour of materials. Quite important are also developments of technologies and equipment for control of thickness and adhesion of thin protective coatings on various bases, corrosion control of underground pipelines by indirect method, acoustic emission control of hydrogen and corrosion cracking in structural materials, etc. 

Although the technology of an MRI scanner is rather sophisticated it does what we have seen other NMR spectrometers do it detects protons Thus MRI IS especially sensitive to biological materials such as... 

Commercial production of acetic acid has been revolutionized in the decade 1978—1988. Butane—naphtha Hquid-phase catalytic oxidation has declined precipitously as methanol [67-56-1] or methyl acetate [79-20-9] carbonylation has become the technology of choice in the world market. By-product acetic acid recovery in other hydrocarbon oxidations, eg, in xylene oxidation to terephthaUc acid and propylene conversion to acryflc acid, has also grown. Production from synthesis gas is increasing and the development of alternative raw materials is under serious consideration following widespread dislocations in the cost of raw material (see Chemurgy). 

The technology of urea production is highly advanced. The raw materials requited ate ammonia and carbon dioxide. Invariably, urea plants ate located adjacent to ammonia production faciUties which conveniently furnish not only the ammonia but also the carbon dioxide, because carbon dioxide is a by-product of synthesis gas production and purification. The ammonia and carbon dioxide ate fed to a high pressure (up to 30 MPa (300 atm)) reactor at temperatures of about 200°C where ammonium carbamate [111-78-0] CH N202, urea, and water ate formed. 

Production of a metal is usually achieved by a sequence of chemical processes represented as a flow sheet. A limited number of unit processes are commonly used in extractive metallurgy. The combination of these steps and the precise conditions of operations vary significantly from metal to metal, and even for the same metal these steps vary with the type of ore or raw material. The technology of extraction processes was developed in an empirical way, and technical innovations often preceded scientific understanding of the processes. 

More recendy, however, the technology of introducing a new functional group to the double bond of allyl alcohol has been developed. Adyl alcohol is accordingly used as an intermediate compound for synthesizing raw materials such as epichlorohydrin and 1,4-butanediol, and this development is bringing about expansion of the range of uses of allyl alcohol. 

It is very difficult to treat MDA as a single entity because the manufacturing processes of PMDA and MDA are essentially identical, with the exception of a separation step. This article focuses on the technology of 4,4 -MDA, and it also includes properties of isomers and oligomeric mixtures when they are of commercial importance. The 4,4 -MDA is a suspected human carcinogen, and therefore special handling of this material is required. AH of the MDA and PMDA produced is consumed in industries that are "destmctive" of MDA s chemical identity. Thus MDA loses its unique chemical identity and is not encountered by household consumers. 

Copolymer technology is progressing along two "fronts." First, new appHcations for copolymers are being found to increase the volume of materials that are already commercially available. One example of this is the rapid growth of styrenic block copolymers sold as asphalt (qv) and polymer modifiers over the past 10 years (Fig. 7). Another is the increased interest in graft and block copolymers as compatihilizers for polymer blends and alloys. Of particular interest are compatihilizers for recycled polymer scrap. 

FIG. 25-63 Typical flow sheet for the recovery of materials and production of refuse-derived fuels (RDF). [Adapted in pait from D. C. Wilson (ed.). Waste Management Planning, Evaluation, Technologies, Oxford Univei-sity Press, Oxford, 1981.]... 

Recommended materials are outlined in the standards. Some of the recommendations in the standard are carbon steel for base plates, heat-treated forged steel for compressor wheels, heat-treated forged alloy steel for turbine wheels, and forged steel for couplings. The growth of materials technology has been so rapid especially in the area of high temperature materials the standard does not deal with it. Details of some of the materials... 

As an indication of the central role that phase diagrams now play in the whole of materials science, the cumulative index for the whole of the 18-volume book series. Materials Science and Technology (Cahn et al. 1991-1998) can be cited in evidence. There are 89 entries under the heading phase diagram , one of the most extensive of all listings in this 390-page index. 

The electronic theory of metallic superconduction was established by Bardeen, Cooper and Schrieffer in 1957, but the basis of superconduction in the oxides remains a battleground for rival interpretations. The technology of the oxide ( high-temperature ) superconductors is currently receiving a great deal of attention the central problem is to make windable wires or tapes from an intensely brittle material. It is in no way a negative judgment on the importance and interest of these materials that they do not receive a detailed discussion here it is simply that they do not lend themselves to a superficial account, and there is no space here for a discussion in the detail that they intrinsically deserve. 

A valuable source of up-to-date reviews of many aspects of MSE is a series of books. Annual Reviews of Materials Science, published for the last 30 years. There has been one extensive series of high-level multiauthor treatments right across the entire spectrum of MSE, in the form of 25 books collectively entitled Materials Science and Technology A Comprehensive Treatment (1991-2000), masterminded by Peter Haasen, Edward Kramer and myself. There have also been three encyclopedias, the Encyclopedia of Materials Science and Engineering (1986), the Encyclopedia of Advanced Materials (1994) and the Encyclopedia of Materials (2001), which last has appeared in both printed and on-line versions and will receive annual updates. 

---