From Stents to Soft Robotics: Why Nitinol Is a Material to Watch

Nitinol is quickly becoming one of the most versatile and in-demand materials in research and development. Known for its unique ability to "remember" shapes and return to its original form after deformation, this nickel-titanium alloy is being used across biomedical, robotics, aerospace, and academic research fields.

Nitinol—also known as nickel‑titanium—is a unique shape‑memory alloy (SMA) with remarkable properties. It can deform at low temperature and return to a preset shape when heated (shape memory), and it can undergo and recover from large strains instantly when stressed above its transformation temperature (superelasticity or pseudoelasticity). 

These features make Nitinol invaluable in transformative applications across biomedical research, soft robotics, aerospace, and materials science.

If you’re a researcher or lab technician looking to explore the potential of smart materials, here’s why Nitinol deserves a place on your bench—and in your materials sourcing plan.

What Is Nitinol? An Overview of the Shape Memory Alloy

Nitinol is an alloy of roughly 50% nickel and 50% titanium, named after its origin at the Naval Ordnance Laboratory (Nickel Titanium Naval Ordnance Laboratory). What makes it unique is its shape memory and superelastic properties:

• Shape memory: After being deformed, Nitinol returns to its original shape when heated above a certain transformation temperature. When cooled below the martensite finish temperature (Mₓ) and deformed, the alloy holds that shape until heated above the austenite finish temperature (Aₓ), at which point it returns to its original form.
• Superelasticity: Above Aₓ, applying stress induces a reversible martensitic phase that allows up to ~8–10 % strain recovery instantly upon unloading—no heating required. It can undergo significant strain (up to 8%) and recover its original shape without permanent deformation.

These unusual properties stem from a reversible phase transformation between two solid-state structures: austenite and martensite.

Why Researchers Choose Nitinol

Researchers across disciplines are turning to Nitinol for its:

• High fatigue resistance - even under cyclic loads typical in biomedical implants (e.g., stents)
• Excellent biocompatibility and corrosion resistance: surface treatments like electropolishing or passivation form a stable TiO₂ layer, reducing nickel release and thrombogenicity
• Tunable transformation temperature:Heat treatment (e.g., ageing at 400–500 °C for 30–120 minutes) precisely adjusts Aₓ depending on alloy composition and processing
• Micro-scale machinability and minimal form factor: Enables fabrication of fine wires, sheets, and micro-actuators ideal for high-precision R&D.

Because of this, it’s particularly well suited to precision applications where conventional metals fall short.

Applications in Biomedical Research: Stents, Implants & More

Nitinol’s biocompatibility and shape memory properties make it ideal for medical devices.

Nitinol is widely used for self-expanding stents, particularly peripheral and vascular ones, due to its shape memory and superelastic behavior which ensures conformability to vessel walls and resistance to recoil

It’s also widely used in:

• Self-expanding stents that deploy automatically in arteries
• Dental arch wires, orthopedic implants, and bone anchors that adjust gradually with body temperature
• Minimally invasive surgical tools
• Bone anchors and spinal implants

Researchers are also exploring new uses, such as:

• Temperature-responsive drug delivery systems
• Shape-shifting scaffolds for tissue engineering
• Micro-actuated implants for targeted treatment

Nitinol in Soft Robotics and Actuation Systems

In soft robotics, Nitinol is being used to create artificial muscles and motion systems that can bend, stretch, and return to shape with heat or electrical current.

Examples include:

• Microscale grippers for surgical tools and micro-manipulation
• Wearable robotics for rehabilitation or human augmentation
• Bioinspired systems that mimic muscle contraction

Because Nitinol components can be made ultra-thin and still produce significant motion, they’re ideal for compact, flexible robotic devices.

Emerging Uses in Aerospace, Optics, and Materials Science

Beyond medical and robotic systems, Nitinol is being studied for:

• Thermally responsive fasteners in aerospace, where parts expand and contract predictably in extreme conditions
• Tunable optical elements, such as adaptive lenses or laser modulators
• Microelectromechanical systems (MEMS), where compact actuation is needed without bulky motors

It’s also being tested in precision systems where vibration damping and flexibility are essential.

Sourcing Nitinol for R&D: Formats, Purity and Procurement Tips

For research applications, Nitinol is typically supplied as:

• Wire (round, flat or ribbon) in various diameters
• Sheet or foil for fabrication or thin-film devices
• Rod or bar for machining or shaping into components

Why Nitinol Demand Is Growing in Academic and Lab Settings

Nitinol sits at the intersection of materials science, mechanical engineering, and biomedical research. It supports innovation in:

• Lab-based prototyping
• Microscale device development
• Cross-disciplinary engineering projects

As more research teams look to integrate smart, responsive materials into their designs, Nitinol offers a tested, reliable option—one that opens doors to new functionality without introducing exotic or hard-to-source compounds.

Key factors to consider:

1. Purity level: For biomedical or precision applications, high-purity Nitinol is essential.
2. Transformation temperature: Needs to be specified based on the intended use.
3. Surface finish and oxide layer: Affects corrosion resistance and performance, especially in biomedical contexts.

At Advent Research Materials, we supply high-purity metals and alloys in small quantities, suitable for R&D and prototyping.

We’re currently assessing demand for Nitinol—if it’s on your sourcing list, let us know.