Correlation between microstructural inhomogeneity and architectural design in additively manufactured NiTi shape memory alloys

Autor: Zhaorui Yan, Jia-Ning Zhu, Darren Hartl, Ton Riemslag, Sean Paul Scott, Roumen Petrov, Marcel Hermans, Jovana Jovanova, Vera Popovich
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: Virtual and Physical Prototyping, Vol 19, Iss 1 (2024)
Druh dokumentu: article
ISSN: 17452759
1745-2767
1745-2759
DOI: 10.1080/17452759.2024.2396065
Popis: Additively manufactured Nitinol (NiTi) architectured materials, designed with unit cell architectures, hold promise for customisable applications. However, the common assumption of homogeneity in modeling and additive manufacturing of these architectured materials needs further investigation because geometric-dependent melt pool behaviour results in inhomogeneous microstructure and thermomechanical properties. This study shows that property inhomogeneity at the mesoscale is one reason for pseudo-linear response and partial superelasticity of the fabricated NiTi body-centered cubic (BCC) architectured materials. We modeled using a phenomenological constitutive relation and additively manufactured NiTi architectured materials with varying relative densities. These fabricated samples showed distinct microstructural textures and compositions that affected their local recoverability. The edge effects and laser turn regions were identified as the causes underlying the observed microstructural inhomogeneity. The dimensionless Fourier number is used to describe the transition of printing modes. This study provides valuable information on rigorous experimental/computational consistency in future work.
Databáze: Directory of Open Access Journals