Physical methods of analysis in metallurgy

Over the last fifteen years or so, there has been a veritable explosion in the number of physical methods proposed by researchers, with several hundred listed by research laboratories. But the most remarkable fact is that many of them, given their obvious practical interest, have not remained at the curiosity stage of university research laboratories, but have found their way into industrial laboratories.

In the field of metallurgy, long limited to optical microscopy and classical chemistry, new physical methods have revolutionized characterization techniques and, above all, the microcharacterization of materials. It is this aspect of microcharacterization – first on the micrometer scale, then on the nanometer scale – that is the subject of this article.

Faced with this rapid evolution in the range of methods available, almost all of which have become highly specialized, the non-specialist metallurgist may feel a little bewildered. The aim of this article is therefore to provide a critical inventory of the most commonly used physical methods, in order to suggest criteria for choice according to the problems posed.

After a quick classification by volume analyzed, excitation and emission modes, information provided and average performance, the most important part will be devoted to a detailed review of the advantages and disadvantages of these various methods, classified into broad categories:

• imaging ;

• elementary analysis ;

• chemical bond ;

• crystallographic structure.

In the final section, these elements enable us to identify the basic principles that lead us to propose selection criteria.