Metallography / Plasterography / Petrography

There is a strong connection between the structure of matter and its properties in materials engineering. Often, exposing the structure, shape, and coatings or characteristics of the material provides a great deal of information to the researcher. For example:
 

Metallography - The structure of the material characterizes the processes of mechanical processing that the material has undergone (rolling, pressing, etc.), thermal treatments performed during production (sealing, relaxation, etc.), surface treatments and hardening (eg carbonization)

Plastography - The structure of the material may reveal layers of different materials that were taken together, spaces in the polymer casting and even discontinuities in the interface with adjacent material or color.

Petrography - The porosity of cladding materials such as flooring, marble slabs and the like is a parameter of the material which is not always exposed in its outer face. The use of the models technique reveals discontinuities, infections and cracks in the material. 
In order for the microbial to be exposed and to distinguish between the different areas of the structure, a metallographic model is required. The steps for the preparation of the model include casting of the part under polymer resin, which are performed: grinding, polishing and abrasion (burning with a solution that exposes the structure of the material). At the end of the process, the structure of the material can be examined using a light microscope.

Steps in preparing a metallographic model:

Cutting - In order to test a specific area, cut it in a cooled and controlled manner. With the maximum dimensions of the final model up to 2 cm in length.

Sharpening and polishing - for the removal of dirt as surface oxides of the model under study, and for achieving surface planarization, grinding is done by a series of polishing papers ranging from coarse paper with grain 80 to fine paper with 1200 grain. After this step, Polishing on which diamond paste is applied with a number of refinements ranging from 15 microns to 1 micron.