Metals are obtained by working metal ores, and they also have very good characteristics such as strong electrical and thermal conductivity, high strength, high melting temperature, and others. Corrosion of metals is one of the most significant defects in the use of metals. Corrosion is a chemical reaction of metals caused by environmental influences in which a material is placed. Most metals undergo corrosion processes, which are generally undesirable. As a result, coating occurs in order to provide some protection of metals. Such coatings play a key role in the protection of materials, some of which will be described through this final work. This paper describes the phosphatification, i.e. the technological process itself, and certain coatings used on steel and iron. Likewise, another type of protection is mentioned of steel brushing where the paper describes which types of brushing exist and how the workpieces are prepared for the brushing process. Furthermore, it is described how the protection of copper and its alloys is implemented and this part of the work specifically emphasized the suffering of copper and brass.