**4. Conclusions**

The algorithm for the structural design of the geometry was proposed. In the framework of the study, a porous cube was chosen for the basic cell. The following assumptions were used: calculation was carried out in an elastic zone; the material is isotropic; and anisotropy appears by the porosity of the basic cell. The iterative algorithm for the structural design was presented. The samples were designed, and the verification of the structural simulations was carried out. The comparison of the maximum von Mises stress for all the samples did not show a significant difference. However, for the structurally designed beam, zones of stress reduction appeared.

The manufacturing was provided using additive technologies. The samples were printed using different directions, and three-point bending tests were performed. Stressstrain curves were obtained for all the samples. In the case of the longitudinal direction printing, the ultimate force of the structurally designed sample was about 10% higher. In the case of the transversal direction printing, the rigidness of the structurally designed sample was almost 40% higher. The analysis of the stress-strain curves for all the samples shows the significant influence of the printing directions on the mechanical properties and demonstrated the need for post-processing.

**Author Contributions:** Methodology and software, P.B., N.K. and O.S.; manufacturing, R.K.; writing review and editing, O.S.; conceptualization, O.S.; methodology, O.S. and P.B.; software, P.B. and N.K.; validation, O.S. and P.B.; formal analysis, P.B. and N.K.; investigation, P.B.; resources, R.K.; data curation, O.S.; writing—original draft preparation, P.B. and O.S.; writing—review and editing, O.S.; visualization, O.S. and P.B.; supervision, O.S.; project administration, O.S.; funding acquisition, O.S. and R.K. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by RFBR, grant number 18-41-160025 p\_a.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data available on request.

**Acknowledgments:** Special thanks to Independent X-ray diagnostic centers Picasso.

**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.
