Page 79 - MSAM-3-2

Materials Science in Additive Manufacturing Mechanical properties of NiTi TPMS

A B C

D E F

Figure 17. Shape memory behavior of sheet-shaped gyroid cellular structure (SGCS) under different strains with different aging times. (A) 0 h; (B) 2 h;
(C) 4 h; (D) 6 h; (E) 8 h; and (F) 10 h.

A B

Figure 18. Shape memory recovery ratio of samples treated with different aging times. (A) Rod-shaped gyroid cellular structure (RGCS); (B) Sheet-shaped
gyroid cellular structure (SGCS).

withstood an increase to 8% compressive strain, while RGCS, likely attributed to the increased elastic modulus
the SGCS-A0, SGCS-A2, SGCS-A4, and SGCS-A10 and compressive strength of SGCS after aging heat
fractured before reaching 8% compressive strain, resulting treatment. In addition, as compressive strain increased,
in a sharp decline in stress. The superelasticity range of irreversible plastic deformation ensued, due to the
SGCS appeared relatively narrow, spanning between 2% accumulation of unrecoverable strain resulting from
and 4% compressive strain. Notably, the stress-strain minor defects such as microcracks and microvoids in the
curves of SGCS exhibited a slight jagged change at 6% LPBF process. On reaching a strain level of 8%, SGCS
strain, suggesting the onset of compression fracture. attained its maximum compressive strength. The internal
The superelastic response of SGCS outperformed that of collapse of the structure resulted in a significant reduction

Volume 3 Issue 2 (2024) 16 doi: 10.36922/msam.3137