Moscow University of Science and Technology MISiS, Moscow, Russia:

E. A. Yuzhakova, Post-Graduate Student of a Chair of Physical Materials Science, e-mail: lee_na@mail.ru

JSC “Giredmet”, Moscow, Russia:
V. T. Beshkarev, Leading Researcher of Laboratory of Rare, Refractory and High-Pure Metals Obtaining Technology

Ural Plant of Gas Centrifuges, Novouralsk, Russia:
K. I. Trofimov, Leading Mathematician of Calculation and Design Engineering Department
S. G. Khomyakov, Head of a Project

Our paper offers the option of a modular device for regeneration of spent powder mixtures after layer-by-layer synthesis of polymetallic items. Depending on variants of the composition of the used powders, the device may include interchangeable modules of electromagnetic, sieve or gas-dynamic classification. High-vacuum and high-temperature degassing module should be included in the powder composition regeneration system to remove adsorbed gases from the particle surface. For the separation of powder composition, formed using two powders of the same fineness and different magnetic properties, it is advisable to use the electromagnetic separation module. In case of using powders with same basis elements and with comparable density values, the gas-dynamic classification module should be applied. Using the methods of mathematical and experimental modeling, it is shown a comparison of the effectiveness of different waste powder mixtures separation types and classifiers such as “zigzag”, “cyclone” and “dust camera”. It is shown that the modular classifier based on dust camera provides the necessary functionality: divides multipowder mixture into fractions of predetermined particle size. The possibility of applying centrifugal classifier with the option of separation of powder mixtures in an inert atmosphere to work with powders based on active metals was discussed. On the basis of relations established in the modeling of vacuum degassing processes of waste classified polymetallic powder mixtures, it was revealed the efficiency of degassing of thin or moving layers of powder. To improve the profitability of additive production of titanium based items it was offered the method for recycling of waste products. The technology involves the sequential operations of hydrogenation, crushing, dehydrogenation, classification and plasma spheroidization to obtain the source powders for use in additive technologies.

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