TSU suggested how to replace scandium in materials for shipbuilding

14 January 2020

Nikolai Kakhidze, a graduate student of the Faculty of Physics and Engineering, has suggested using diamond or aluminum oxide nanoparticles as an alternative to expensive scandium for hardening aluminum alloys. The new material will cost 4 times less than the scandium-containing analog with fairly close physical and mechanical properties.

Currently, many shipbuilding companies are striving to replace heavy steel with light and ultra-light materials. In addition to increasing carrying capacity, this can be advantageously applied to reduce fuel consumption, reducing harmful emissions into the atmosphere and increasing the mobility of the vessel and accelerating the delivery of cargo. Enterprises in the transport and aerospace industries are also interested in new materials.

Aluminum matrix composite materials modified with scandium became a good substitute. However, due to the high cost of scandium, an active search is underway for a more affordable modifier. Nikolai Kakhidze proposed replacing scandium with diamond or aluminium oxide nanoparticles. His task will be to develop a method for the correct introduction of nanopowders into a metal melt.

When directly introduced into the melt, the nanoparticles are aggregated into agglomerates, oxidized, and not wetted, and they form pores around themselves. As a result, unwanted impurities are obtained instead of hardening particles. In the laboratory of high-energy and special materials at Tomsk State University, Sergey Vorozhtsov has already developed scientific and technological approaches for dispersed hardening of aluminum and magnesium that ensure the correct introduction of refractory nanoparticles into the melt and eliminate the problems of wettability and flotation.

- Based on the development of my colleagues, my project proposes the following solution: nanopowders are de-agglomerated (evenly distributed) in a micro-sized aluminum powder using several technological operations. Then a ligature is synthesized from this mixture that is sufficiently technological and convenient for industrial use on an industrial scale. When the ligature is introduced into the melt, external fields are processed to uniformly distribute the nanoparticles and further increase the wettability. The correct introduction of nanoparticles can improve the physical and mechanical properties of the initial alloy, - Nikolai Kakhidze explains the essence of his work.

Nikolai Kakhidze plans to receive the first experimental batches of ligatures with nanoparticles for their subsequent introduction into the melt by the end of 2020. In 2021, it is planned to obtain trial castings and protect intellectual property rights.