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Yang, et al.

A
D

B

C

Figure 4. Optical microstructure of laser-processed parts and the corresponding XRD patterns. (A) Mg. (B) Mg-Sc. (C) mMg-Sc. (D) XRD
patterns.

for mMg-Sc specimen, a single-phase microstructure A B
was formed. The corresponding XRD patterns, as
depicted in Figure 4D, also revealed the same results.
In fact, SLM is a rapid prototyping technology using
high-energy laser beam as processing heat source
and has great potential in the preparation of non-
equilibrium alloy. It was believed that the laser has the C D
characteristics of high-energy density and small action
area. Laser radiation on the non-equilibrium alloy
powder can make the powder skip the crystallization
area and melt at a very high heating rate, and then,
the micro-molten pool is cooled rapidly through
non-interface heat conduction, which is much higher
than the critical cooling rate required to form the
non-equilibrium alloy [42,43] . Thus, the deposited Figure 5. The electrochemical test results of samples. (A) OCP
layer of non-equilibrium alloy structure is obtained. curves. (B) Polarization curves. (C) Nyquist plots. (D) |Z|-
More importantly, SLM can obtain parts through the frequency plots and phase angle frequency plots.
superposition of deposition layers [44,45] . A number of
studies have proven that SLM process is effective in MA and then processed by SLM. Results showed that
preserving the metastable phase. For instance, Hugo metastable Al Fe parts were successfully obtained at
5
2
et al. [46] produced fine metastable Al-Fe powders by suitable laser processing parameters.
International Journal of Bioprinting (2022)–Volume 8, Issue 3 101