Читать книгу Monument Future - Siegfried Siegesmund - Страница 424

The analysis with 3D Optical microscopy profilometer has highlighted quantitatively how a routine mild cleaned can alter the surface of a stone material.

The analyses have highlighted that in an abrasion-resistant material such as marble the effect of the impact of the grains of sand on the surface varies in relation to the angle of impact of the single grain, which in turn affects the roughness of the material by altering its surface polishing.

In this research, three materials of different hardness and abrasion resistance were analysed, and in fact it was observed that according to the morphology of the samples, the alterations generated by the treatment increase the roughness and in the case of the samples that were not very resistant to abrasion, such as the Noto Calcarenite Lime stone, also involved significant loss of material compromising its macroscopic appearance.

In an abrasion-resistant material, such as Serena stone, which apparently does not show any alteration of the surface visible to the naked eye, an increase in roughness is observed microscopically which increases the surface absorption.

This new technique is applicable as an alternative and/or in addition to optical color measurements during laboratory tests and complementary to investigations such as SEM (Schroettner et al. 2006).

274As a future perspective of the research, the possibility of creating an algorithm for the evaluation of surface porosity variations is being evaluated by comparing the data obtained with Alicona, mercury porosiment and micro-CT.