Metallography is undoubtedly one of the most useful techniques for addressing the numerous questions posed by archaeologists about metal artifacts. The most frequent questions include:

∎ What is the nature of the metal or alloy which the object is made of?

∎ Where did the object and/or its raw materials originate?

∎ What technologies were employed in producing the object?

∎ How old is it?

Many aspects of a metal artifact's history are imprinted in its microstructure (i.e., the structure of the material as revealed under the microscope after appropriate surface preparation). The artifact has a story to tell and the role of the archaeometallurgist is to read and translate the story by studying and interpreting the microstructure. In most cases it is productive to supplement the information obtained from optical microscopy by using other analytical techniques. This will be illustrated below.

Although it is frequently not possible to obtain definitive answers to the above questions, this does not necessarily mean that the analysis has served no useful purpose. For example, it may be just as important to demonstrate what an artifact is not as to prove what it is. Eliminating some of the possible identifications may be a valuable contribution.

Consider the first question: What material is the artifact made of? It is normally essential to perform elemental analyses in order to identify the material. Nevertheless, metallography is a useful first step in answering this particular question. Furthermore, the specimen prepared for optical microscopy can be used without further preparation for other analytical techniques (such as electron probe microanalysis) which can yield an elemental analysis. As will be demonstrated in the following case studies, metallography is of great value in assessing the forms of impurities in metallic materials. This is highly useful information which elemental analysis cannot provide.

The next major step in the development of fusion power involves the design, construction, and operation of an experimental power reactor. The general objective of this type of device is to demonstrate key plasma physics, materials, and engineering performance under conditions that approach those considered necessary to establish the technical feasibility of fusion power. This device is generally perceived to be a tokamak configuration that operates on the deuterium-tritium (D-T) fuel cycle, which would produce several hundred megawatts of fusion power. Although a number of conceptual design studies on this type of device have been conducted, the current effort is focused on the International Thermonuclear Experimental Reactor (ITER) activity, a joint undertaking of the European Community (EC), Japan, the United States, and the Soviet Union, conducted under the auspices of the International Atomic Energy Agency (IAEA).

The development of fusion power as an energy source depends to a large extent on the proper selection of materials for the various components. these materials will be exposed to a wide variety of conditions such as plasma particle and neutron radiation, high thermal fluxes, large thermal and mechanical stress, various chemical environments, and high magnetic fields. In order to achieve the high performance desired for a commercial power reactor, considerable materials development will be required. Because of the relatively near term time scale projected for ITER and the limited objectives, more conventional materials with more extensive data bases will be used where possible. Even so, a substantial materials development program is required to support a test reactor like ITER.

The Division of Applied Physics of the Commonwealth Scientific and Industrial Research Organization performs research in the physical sciences to benefit Australian industry and also staffs the National Measurement Laboratory, underpinning the Australian measurement system. CSIRO is the major government-funded research organization in Australia, employing approximately 7,000 people, based in 30 divisions, and whose interests range from the agricultural and livestock areas through prospecting, mining, and manufacturing to information and communication technologies. The general mix of work in the divisions includes a proportion of basic science and a significant involvement in contract research with relevant Australian industries.

The Division of Applied Physics is one of the oldest divisions and celebrates its 50th Jubilee in 1988. This year is also the 200th anniversary of European settlement in Australia and the 25th anniversary of the founding of the Australian Institute of Physics. It was a busy year for the laboratory!

Materials science research in the Division developed from the needs of the standards research program, passed through a period of primarily basic research, and now concentrates on industrial research and the underlying basic research. Four areas which exemplify this progression toward applied research and development are described in this article.

Thin film research started in the Division in the 1950s to produce optical coatings, driven by the requirements of a developing standards research program, and the needs of an astronomy program to study the surface of the sun spectroscopically.

Burned periclase brick became a commonly used refractory material during the 1940s and early 1950s in the steel-making industry. Unfortunately, periclase brick easily reacts with water or water vapor and results in dimensional instability, i.e., a volume expansion. This may lead to the mechanical failure of any article made from it. Considerable research has been performed in the past 30 years to suppress the hydration susceptibility of magnesia refractory.

Boron has been found to be extremely effective in improving the hydration resistance of magnesia. It can be added to magnesite, brucite, light calcined magnesia or it can be deposited on post dead burned magnesia. However, the use of boron decreases the hot loading bearing properties of the magnesia and the dissolution of the boron into certain grades of steel may adversely affect their mechanical properties. Moreover, the addition of boron compounds requires a high-temperature calcination, normally higher than 1600°C, which has been proven uneconomical.

Other dopants, incorporated either on the surface or in the bulk, have been reported to have various effects on the hydration susceptibility. The ultimate goal of the work reported here is to determine if there is a correlation between the hydration susceptibility of MgO having various cation substitutions for Mg and the energies of the resulting lattices.

Small inorganic particles with a narrow size distribution have been prepared from aqueous and organic solutions under varied temperatures, pressures, and concentrations. This article reviews the preparation of such particles from microemulsions and liquid crystals and shows how these amphiphilic association structures can have a pronounced influence on the size, shape, and even chemical composition of the precipitated particles.

Surfactants associate in the presence of water to form micelles and lyotropic mesophases. This is a consequence of the molecular geometrical packing requirements, superposed on the dissolution behavior of these substances. Associated structures that have shapes with the lowest free energy are preferentially formed. A balance is attained between the interactions of the hydrophobic portions of the surfactant, reducing the unfavorable contact with aqueous environs and the interactions between the headgroups. The composition regions of these different phases have been widely studied. Micelles exist as normal and reversed structures (Figure 1), while the liquid crystalline phases show a variety of structures which have been studied in great detail.

Figure 1 gives a simplified example of the structural conditions in different parts of a phase diagram of the three components water/surfactant/amphiphilic substance (e.g., medium chain length alcohol). The interaction between water and the surfactant is sufficiently pronounced to permit the formation of reversed micelles. The association structures of different regions shown in Figure 1 include normal (L1) and reversed micelles (L2). The hexagonal phase (E) consists of a hexagonal array of cylinders with the hydrocarbon chains situated in the center of the cylinder, while the reverse hexagonal phase (F) is built of cylinders with aqueous centers. The lamellar phase (Lα) is made up of infinite sheets of bimolecularly arranged surfactant molecules separated by aqueous layers. The physical properties and reasons for the formation of such lyotropic phases have been discussed extensively.

It is an honor to receive the Arthur von Hippel Award, and to become a member of such a select club! It is also a great pleasure to be introduced by my friend Harvey Brooks, who, with his wife Helen, were the first Americans to greet me on my first trip here in 1953.

What has an aging theoretical physicist to do with such a young and budding society as yours? I can only comment on this difficult question by reflecting on the way some of my work has proceeded, and what light this might throw on the development of materials research. I will concentrate on two topics which have been at the core of my work.

I stated research in 1948, under my cousin Charles Crussard, at the Laboratory of Metallurgy of the Paris School of Mines, after a thorough training in mathematics, some training in classical physics and chemistry, and two years of more technical training in mining and metallurgy. I started pulling at test samples and tried to get interested in internal friction. I also learned about x-rays on an old tube set up by my father Edmond Friedel in 1920 at Maurice de Broglie's laboratory, to check the prediction of a layer structure for “smectic” mesophases made by his own father Georges Friedel. I finally used this tube in a very simple piece of experimental work where I measured the angles made at triple nodes by grain boundaries in a sheet of recrystallized aluminum. The idea was to deduce how the grain boundary tension varies with the relative misorientation of the two grains, having checked that the tension does not vary much with the orientation of the boundary with respect to the crystals, a remark that justifies the method.

Oxide compounds have been extensively studied through the years because they exhibit a broad spectrum of electrical, magnetic, and optical properties providing both scientific and technological interest. Most oxides are insulators, but a few of them (e.g., LiTi2O4 or BaPb1−x BixO3 show metallic conductivity and even superconductivity at low temperatures. The discovery of superconductivity at 35 K by Bednorz and Müller in the cuprate La-Ba-Cu-O system prompted the search for other high Tc compounds among this oxide family. Superconductivity above liquid nitrogen was then rapidly achieved with the Y-Ba-Cu-O system (Tc=90 K) and subsequently, with the Bi-Sr-Ca-Bu-O and Tl-Ba-Ca-Cu-O systems, Tc was raised to 110 K and then 125 K.

A common feature of these new high Tc cuprates is that they belong to the large family of materials, termed perovskites, which have been studied over the years because of their ability to absorb or lose oxygen reversibly (i.e., for their nonstoichiometry in oxygen). It had been previously established in the field of superconductivity that Tc is extremely sensitive to compositional stoichiometry.

The Interuniversity Microelectronics Center, Leuven, Belgium (IMEC) is one of the world's largest independent research centers for microelectronics. It was established in 1984 by the Flemish government as a part of a comprehensive program to promote high technology in Flanders, Belgium. Benefiting from existing experience available mainly at the University of Leuven, IMEC moved into its present facilities in 1986 (Figure 1).

The Center covers a wide range of research topics in the microelectronics domain—VLSI systems design methodologies, advanced semiconductor processing, materials, packaging, and more.

About 50 people work on computer-aided design, developing a series of “true” silicon compilers: CATHEDRAL. With this software, ASIC (application specific integrated circuit) design becomes extremely attractive, since CATHEDRAL covers design from the high system level down to layout.

INVOMEC, the training division of IMEC, supports universities in ASIC design. It trains people for both educational institutes and industry in chip design, makes available the necessary software, and has a well-established Multi Project Chip—Multi Project Wafer service.

The Processing Technologies and Materials Divisions involve about 200 people and have a 3,600 m2 clean room at their disposal. The clean room consists of a 20% class 10 area with a fast-turnaround prototyping line and an 80% class 1000 area.

IMEC's objectives are: to perform research in the microelectronics field, supporting both industry and universities, and to stimulate the microelectronics industry in Flanders.

IMEC performs research on both silicon and III-V technologies.

The word phytolith means “plant rocks.” Phytoliths are mineral deposits that form in and between plant cells. Any mineral deposit may be considered a phytolith, although most recent research has focused on opaline silica. Silica seems to be widespread in at least some plant families and is resistant to dissolution in a pH less than 9. Silica phytoliths therefore have the potential to be useful microfossils that can be helpful in the documentation of prehistoric environment and economy.

Identifiable shapes rather than amorphous deposits are a necessary characteristic for useful microfossils. Several plant families have long been known to be consistent accumulators of identifiable silica bodies: Gramineae (grass), Cyperaceae (sedge), and Equisetaceae (horsetail). Phytoliths from the Gramineae are especially well known; specialized silica-accumulating cells produce distinctively shaped phytoliths. However, other families have also been shown to produce significant amounts of identifiable phytoliths. Ulmaceae (elm), Fabaceae (bean), Cucurbitaceae (squash), and Compositae (sunflower) are a few examples of dicotyledonous families that commonly produce phytoliths. Some families, such as the Labiatae (mint), have yielded little or no identifiable phytoliths to date. However, further study may indicate phytolith production in particular species.

While high Tc superconductivity was first discovered in bulk material, it was apparent that thin films of these materials, particularly the compound YBa2Cu3O7-δ, would be of great interest to both science and technology. In this sense the development of these materials parallels a similar history in the low Tc materials. Initially, most of the low Tc materials of interest were single element metals such as Nb, Pb and Al in bulk form. Later work, mostly in magnets, led to the development of compounds or alloys of such metals as Nb-Sn, Nb-Ti, and many others. However, many physical and technological investigations required thin films with thicknesses in the range of 0.1-10μm. Microwave, infrared, and critical current studies are examples of some of the scientific uses of thin films. A few examples of the applications would include josephson junction-based digital computer circuits, SQUID (Superconducting Quantum Interference Devices), transmission lines, and interconnects and rf mixers. These studies are also of great interest in the high Tc materials. It is readily apparent that scientific and technological developments in superconductivity are closely interwoven.

The high level of interest in thin films can be appreciated by observing that it was barely a few months after the announcement of superconductivity above 77 K that the first films of these complex, multi-element materials, superconducting at about 86 K were announced. These early efforts at thin film fabrication were generally accomplished using multi-element deposition techniques but subsequent development has seen many varieties of film fabrication techniques used quite successfully to fabricate high-quality films.