Metallographic Analysis


  • Macrographic examination of fracture surfaces
  • Examination of casting defects and segregation (ASTM E381)
  • Examination of welds (UNI EN 1321)
  • Structural defects of welds
  • Fibers flow in forged parts


  • Metallographic microstructure of ferrous and nonferrous alloys.
  • Evaluation of the effectiveness of heat treatments
  • Microstructure and distribution of graphite in cast iron (UNI EN ISO 945)
  • Content of non-metallic inclusions in steels (ASTM E45, DIN 50602, UNI 3244)
  • Apparent thickness of ferritic and austenitic grains in steels (UNI EN ISO 643, ASTM E112, UNI 3245)
  • Classification of strip structure in case-hardened steels (UNI 8449)
  • Carbide distribution in bearing steels (ASTM A892, SEP 1520, ISO 5949)
  • Porosity, unbound carbon and phase structure in cemented carbide (UNI 5825, ISO 4505, UNI EN 24505, UNI EN 24499)
  • Decarburization depth with micrographic examination (UNI EN ISO 3887)
  • Heat treatment of metallographic specimens
  • Thickness of surface hardening treatments
  • Thickness of the galvanic layers

The choice of a metal alloy for a particular purpose cannot always be made on the basis of previous data. The properties of the material may change during processing in such a way as to affect, sometimes irreversibly, the properties required in service. It follows that the control of construction materials, whether ferrous or non-ferrous, is now an indispensable phase within the production cycle and affects various product areas. Optical metallography, an extremely versatile and rapidly applicable technique, allows the characterization of the test specimen from a structural point of view, providing immediately a great deal of information both on the raw material supplied and on the finished product, which may have undergone heat treatment. Together with hardness measurement and chemical analysis, the method provides a valid tool for the physical characterization of the material under investigation. The microstructure is highlighted in the material by chemical etching of the appropriately polished surface on supports of defined grain size. The APM metallography laboratory has about 200 different etching solutions, which are used depending on the type of material to be examined and the features to be highlighted.