Study of influence of additive wire-arc manufacturing modes on microstructure of AA7075 alloy

The article discusses the wide application of aluminum alloys in various industries, as well as the necessity to increase their strength to meet the requirements of modern technologies. An important point is to investigate the evolution of nanoscale precipitates in AA7075 alloy, in order to improve the mechanical properties of the material. Manufacturing of aluminum alloy parts by additive method allows you to achieve a high level of productivity and, if necessary, to exceed mechanical standards for these materials. Particular attention is paid to structural phase state studies, which are necessary for the development of new technologies based on additive manufacturing, such as surface cladding of aluminum alloys. The study showed that the surface cladding mode (Ar flow rate ≈ 10 l/min, surface cladding speed 100 mm/min, current — 70–80 A, voltage — 15.8 V, wire feed speed — 4 m/min) provides the best results in terms of quality and stability of the cladding process. The manufactured blanks had a dense structure with no visible cracks and the porosity percentage was low. This indicates to the possibility of using this mode for the production of highquality cladding materials. The MIG welding process using constant optimal technological parameters allows to obtain aluminum alloy AA7075 with desired microstructural properties by additive manufacturing method. Strengthening phases in the alloy help prevent crack growth during mechanical testing, and the morphology of equiaxed grains may contribute to uniform stress distribution and increase the strength of the material. It is important to note that large columnar grains in the fusion zones can affect the mechanical properties of the material and additional studies may be required to determine their effect on the overall strength of the alloy. The study was funded by the Russian Science Foundation grant No. 22-79-10245, https://rscf.ru/project/22-79- 10245/.