Page 19 - MSAM-1-4

Materials Science in Additive Manufacturing Y O influence in heat-treated LPBF IN718 composite
2 3

A

B

C

Figure 13. Scanning electron microscopy (SEM) images showing the grain boundary of sample 1275A-Y (A). High-magnification SEM images with EDX
mapping spectra of the segregated (B) and non-segregated (C) areas.

A B 1075A-0, the distribution of the γ′ and γ′′ precipitates is
expected to follow the same trend.
Thus, while it is true that the presence of γ′ and γ′′
precipitates after aging treatment increases the strength of
both Y O -reinforced and monolithic samples significantly,
3
2
the distribution of the precipitates is shown to be affected by
C D the addition of the reinforcement particles, which, in turn,
affects their effectiveness. The lack of proper precipitation
in the region far away from the grain boundaries in sample
1275A-0 affects the mechanical properties of the heat-
treated monolithic sample negatively. Taken together, the
higher strengths of the composites are the result of the
increased Orowan strengthening from a significantly higher
Figure 14. Scanning electron microscopy images showing the precipitates number of nano-sized precipitates, the grain boundary
in sample 1275A-0 near grain boundary (A) and far from grain boundary
(B), and in sample 1275A-Y near grain boundary (C) and far from grain strengthening effect, and the γ′ and γ′′ precipitates being
boundary (D). GB: grain boundary. distributed more homogeneously.

Volume 1 Issue 4 (2022) 13 https://doi.org/10.18063/msam.v1i4.25