Metallography

D. A. Scott, Metallography and Microstructure of Ancient and Historic Metals, The Getty Conservation Institute, Matina del Rey, Calif., 1991. 

Microscopes are also classified by the type of information they present size, shape, transparency, crystallinity, color, anisotropy, refractive indices and dispersion, elemental analyses, and duorescence, as well as infrared, visible, or ultraviolet absorption frequencies, etc. One or more of these microscopes are used in every area of the physical sciences, ie, biology, chemistry, and physics, and also in their subsciences, mineralogy, histology, cytology, pathology, metallography, etc. 

Facts Mbout the Metallography of Titanium, RMI Company, Nile, Ohio, 1975. 

McCall, J. L., and P. M. French (eds.). Metallography in Failure Analysis, Plenum Press, New York, 1978. 

A whole science, called metallography, is devoted to this. The oldest method is to cut the alloy in half, polish the cut faces, etch them in acid to colour the phases differently, and look at them in the light microscope. But you don t even need a microscope to see some grains. Look at any galvanised steel fire-escape or cast brass door knob and you will see the grains, etched by acid rain or the salts from people s hands. 

The equilibrium constitution of an alloy can be determined experimentally by metallography and thermal analysis (described later). If the pressure is held constant at 1 atm., then the independent variables which control the constitution of a binary alloy are T and Xr or Wg. 

Fig. A 1.34. Dendrites of silver in a copper-silver eutectic matrix, x330. (After G. A. Chadwick, Metallography of Phase Transformations, Butterworth, 1972.)...

Sauveur, A. (1916, 1918, 1926, 1938) The Metallography and Heat Treatment of Iron and Steel (successive editions) (McGraw-Hill, New York and London). 

Smith, C.S. (I960) A History of Metallography (The University of Chicago Press, Chicago). 

Figure 6.3(b) is a good example of the beautifully sharp and clear images of dislocations in assemblies which are constantly being published nowadays. It is printed next to the portrait of Peter Hirsch to symbolise his crucial contribution to modern metallography. It was made in Australia, a country which has achieved an enviable record in electron microscopy. 

This approach is an alternative to quantitative metallography and in the hands of a master gives even more accurate results than the rival method. A more recent development (Chen and Spaepen 1991) is the analysis of the isothermal curve when a material which may be properly amorphous or else nanocrystalline (e.g., a bismuth film vapour-deposited at low temperature) is annealed. The form of the isotherm allows one to distinguish nucleation and growth of a crystalline phase, from the growth of a preexisting nanocrystalline structure. 

In Russia, after many years of a successful but purely metallurgical journal entitled Fizika Metallov i Metallovedenie (the last word representing knowledge of materials and not, as I had supposed, metallography (Rabkin 2000)), a group of influential materials scientists in 1997 started a journal entitled Materialovedenie, which word I believe to be the best current Russian form of materials science . In spite of the editors best efforts, the journal is finding it difficult to break away from a metallurgical focus. 

Gcfrorene, n. something frozen, ice cream, ice. Gefiige, n. structure texture, bed, stratum system, order, -art, /. kind or type of structure. -bestandteil, m. structural constituent, -lehre, /. science of structure, specif, metallography. 

The corrosion behaviour of different constituents of an alloy is well known, since the etching techniques used in metallography eu e essentially corrosion processes which take advantage of the different corrosion rates of phases as a means of identification, e.g. the grain boundaries are usually etched more rapidly than the rest of the grain owing to the greater reactivity of the disarrayed metal see Sections 1.3 and 20.4). 

Brammar, 1. S. and Dewey, M. A. P., Specimen Preparation for Electron Metallography. Blackwell, Oxford (1966)... 

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