Bauman Moscow State Technical University, Moscow, Russia:

A. G. Grigoryants, Head of “Laser Technologies” Department, Doctor of Technical Sciences, professor, e-mail: mt12@bmstu.ru
D. S. Kolchanov, Associate Professor of “Laser Technologies” Department, Candidate of Technical Sciences, e-mail: kolchanovdmitriy@gmail.com
A. A. Drenin, Assistant of “Laser Technologies” Department, Postgraduate Student, e-mail: drenin@inbox.ru
A. O. Denezhkin, Postgraduate Student of “Laser Technologies” Department, e-mail: denezhkin.anton95@gmail.com

Selective laser melting (SLM) technology is a promising method for manufacturing complex parts from many metals and alloys. Copper and copper alloys are widely used in industry due to its high thermal conductivity and low resistivity. The use of chromium as an alloying element can increase the heat resistance of copper and its mechanical properties. In this work, samples were made of heat-resistant copper alloy ПР-БрХ to determine their mechanical properties and porosity values. Before the experiments, particle size, morphological and chemical analysis of the powder was carried out. Samples were prepared using the Additive Solutions D250 selective laser melting facility and a multidirectional laser scanning strategy for the powder layer. As a result of the experiments, samples with porosity of less than 5% were obtained. Which were then subjected to tensile tests and computed tomography. However, some samples were subjected to heat treatment. The test results showed that σ_0.2 averages 166.3 MPa, σ_в — 198 MPa, σ_p — 42 MPa, ψ — 8.9%, δ — 3.2%. It was also revealed that heat treatment of samples leads to a decrease in strength properties while maintaining plastic.
The research was conducted under financial support of the Russian Foundation of Basic Research within the framework of the scientific project No. 18-38-00940\19.

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