DOI: https://doi.org/10.33994/kndise.2021.66.55

O. Koshel

The study of relief marking of metal objects is one of the constantly demanded areas of expert research, especially for objects such as weapons and vehicles.
The question of choosing a research method for these objects, which is constantly topical for an expert, acquires particular relevance in the case of rare and historical objects, new expensive products.
In the last decade, a non-destructive method of magneto-optical imaging, which was developed at the Kyiv Polytechnic Institute more than 20 years ago, has been successfully applied abroad for these studies in 40 countries. During this time, the technical implementation of the method has been developed, the technical components of the complex have been significantly improved and changed.
In 2008 basing on the results of practical application on specially designed test objects, including those with three thicknesses of paint coatings, the developers carried out studies in which they assessed the sensitivity of magnetic powder, electrochemical and magneto-optical methods.
Obtained results demonstrated a higher sensitivity of the magneto-optical method for thin-walled objects and the sensitivity for thick-walled objects is not worse than other methods.
Practical application of the modern REGULA 7517 complex in expert studies under various operating conditions confirms its high sensitivity, testifies to the high speed of operation, reliability, autonomy of the complex and wide temperature conditions of use.
The high efficiency of the non-destructive method of magneto-optical imaging makes it possible to consider it as one of the most promising methods in trace studies, as well as in materials science studies, where information on the state and structure of the surface and near-surface layers of metal objects is needed.

Key words: relief marking, restore of deleted marking, non-destructive method, magneto-optical imaging