International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Direct Metal Laser Sintering (DMLS) is a revolutionary technology that allows a production of fully functional metal parts directly from a 3D CAD data, eliminating the investment to production tools and technologies which brings considerable cost and time savings. Metal parts made by DMLS technology are fully comparable with casted or machined parts. A range of application of DMLS technologies is very wide – from prototypes, through short-run production to final products. Advantages of DMLS technology are arising along with complexity of parts – more complex geometry of parts (in terms of shape and occurrence of the detail) make DMLS technology even more economically effective.

The subject of this study is electrochemical and structural characterization of nano-dimenzioned composite electrode materials for hydrogen evolution consisted of Co, Pt or CoPt metallic phase and TiO2, both grafted on multiwalled carbon nanotubes (MWCNTs) as a support material. The main idea was to replace platinum entirely or to some extent as an electrode material. The electrode materials with different The common composition of the studied electrode materials was 10%Me + 18%TiO2 + MWCNTs, where Me = Pt, CoPt (1:1, wt.), CoPt (4:1, wt.) and Pt. The structural and surface changes, as well as their influence on electrocatalytic activity were analyzed by means of XRD, TEM, SEM and FTIR. It was found that Co considerably reduces Pt particle size, from 11 nm (in pure Pt metallic system) to 3–4 nm (in mixed CoPt systems). This is a reason for better activity of the electrode material with CoPt (1:1) metallic phase than that with pure Pt, while the CoPt (4:1) with very low quantity of Pt approaches the acitivity of the electrode material with pure Pt.

The market of precious metals in the world is studied. The requirements for the standard of gold, silver and platinum ingots are named. Factors influencing the world market of precious metals are revealed. Forms of market organization are described. The dynamics of gold, silver, platinum and palladium production in 2010 – 2019 are given. The tendencies of development of the world market of precious metals and the market of precious metals in Ukraine are named