Application of Electron Beam Welding Technique for Joining Ultrafine-Grained Aluminum Plates

The present study is the first attempt to join ultrafine-grained materials by electron beam welding. The aim of the study was to check the feasibility and effectiveness of this type of welding for thermally unstable materials. The results obtained are of high interest, while the welding did cause a decline in mechanical properties, the results were comparable to those obtained using solid-state welding, but with a significant advantage of narrower fusion- and heat-affected zones.

Модель растворения пор на границах зерен при отжиге ультрамелкозернистого алюминиевого сплава

A theoretical model which describes the mechanism of pore dissolution at grain boundaries in ultrafine-grained materials during the ageing annealing is suggested. Within the framework of the model, pore dissolution occurs due to the emission of vacancies and the climb of grain-boundary dislocations along the grain boundary towards the pore. It is shown that in this case there is a significant decrease in the total energy of the system. The results of the model are in good agreement with the available experimental observations of pore dissolution during annealing of ultrafine-grained Al-Zr alloy.