INCREASING THE CORROSION RESISTANCE OF ALUMINUM ALLOYS (Al-Cu, Al-Mg, Al-Mn) BY ADDING MICROALLOYING ELEMENTS IN ITS COMPOSITION

The corrosion resistance of aluminum alloys can be increased by adding various microalloying elements to their composition. The article analyzes the change in corrosion resistance of aluminum-copper, aluminum-magnesium and aluminum-manganese alloys with the addition of germanium. In this case, the samples contained different amounts of germanium: from 1% to 3% of the batch in each sample. The samples were melted in resistance furnaces at a temperature of 750° C and cast into molds. Cast samples were mechanically processed and their corrosion resistance was determined in a solution of 3% NaCl + 0.1% H2O2 (hydrogen peroxide). Corrosion resistance tests were carried out for 90 days. After testing, the surface of the samples was examined under a microscope for oxidation. The degree of oxidation is used to determine the change in corrosion resistance of the samples. In addition, the samples were analyzed for changes in their microstructure under the influence of germanium. The microstructure of the samples was analyzed using a LABO MET-1 microscope for grain dispersion. The germanium element forms a solid solution with the aluminum element (Al3Ge), which restricts the movement of dislocations in the alloy and enhances the properties of the alloy. The germanium element included in the samples contributed to a decrease in corrosion resistance and grain dispersion. It was determined that the corrosion resistance of the sample surfaces improved by 32-40%. The study is covered in detail in the article, and the authors' conclusions are presented at the end of the article.