In simple terms: you can print it, but it's not "springy" enough — it breaks too easily.
Nitinol (nickel-titanium alloy) is widely used in medical devices and high-performance engineering due to its superelasticity and shape-memory properties. But for years, 3D printed nitinol parts have had a critical flaw: their deformability is only about half that of conventionally manufactured nitinol, and they tend to be more brittle.
A Different Approach: Don't Change the Material, Change the Design
Rather than taking the traditional route of "tweaking the formula," the research team at IMDEA Materials Institute and the Technical University of Madrid (UPM) started from structural design. They developed an algorithm-based design framework to create interwoven mesh, spherical, and ring structures — it sounds like weaving, but these are actually printed layer by layer using Laser Powder Bed Fusion (LPBF) technology.
The results were surprising: simply by altering the geometry, they could tune stiffness, load-bearing capacity, energy absorption, and toughness across several orders of magnitude. In other words, without changing the material at all, just by "weaving," they doubled performance.
Validation: What You Print Is What You Designed
To ensure precision, the team scanned printed samples with computed tomography (CT) and compared them layer by layer against digital models from slicing software. The results showed that these structures are not only among the most complex woven nitinol components ever created, but also fully printable without the need for additional supports.
Study lead author Carlos Aguilar Vega stated: "This is the first demonstration that structural design can effectively compensate for the mechanical drawbacks inherent to current 3D printing processes." Co-author Professor Andrés Díaz Lantada called it "a breakthrough in additive manufacturing of superelastic alloys."
we used to focus on improving materials, but now we've discovered — if you get the structure right, you can work around the material's old problems. For fields like medical devices and aerospace, which demand exceptional elasticity and precision, this means greater design freedom and room for performance improvement.
