Mechanical characteristics of laser-deposited sandwich structures and quasi-homogeneous alloys of Fe-Cu system

The laser metal deposition approach implements a unique opportunity for controlling the fabrication of functionally graded and sandwich structures from different metal powders for artificial physical proper-ties management. In this study, the quasi-homogeneous alloys were fabricated by the simultaneous feed of bronze and steel powders from different feeders of the LMD installation and the gradient structures by alternating deposition of the materials. The resulting alloys consisted of 50 wt% -50 wt% and 25 wt% -75 wt% non-gradient bronze-steel parts and sandwich structures of alternating 250 -lm-height steel and bronze layers. The alloy based on aluminum bronze demonstrated the highest ultimate tensile strength (838.6 MPa). Its yield stress amounted to 665 MPa, strain-to-fracture - 0.035, Poisson's ratio - 0.23, and modulus of resilience - 1.03 MJ/m3. A digital image correlation approach was applied to study the char-acter of major strain distribution in the fabricated specimens and localizations of strain concentrators and compare them with all specimens' failure areas. Fractography analysis showed a predominantly brittle character of failure. Investigated materials are expected to be applied as interface regions of Fe-Cu system functionally graded structures.(c) 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

The laser metal deposition approach allows for controlling the fabrication of functionally graded and sandwich structures from different metal powders. Quasi-homogeneous alloys and gradient structures were successfully fabricated using bronze and steel powders. The alloy based on aluminum bronze showed the highest ultimate tensile strength and modulus of resilience.