Havar® Foil

Havar® Foil is a cobalt-based, non-magnetic alloy foil prized for its extreme mechanical strength, corrosion resistance, and fatigue durability under high-pressure, high-radiation conditions. Composed of Co (42%), Cr (20%), and Ni (13%) among others, it exhibits tensile strength exceeding 1860 MPa and a melting point near 1480°C. Its primary uses span cyclotron targets, radiation shielding, and energy-dense environments in medical isotope production and nuclear research. Specifically, Havar® Foil is widely implemented as the entrance window for pressurized 18F aqueous targets used in PET radiopharmaceuticals. Enhanced designs include sputtered niobium (Nb) layers to improve chemical inertness while maintaining Havar’s superior mechanical performance. This Nb-coating significantly reduces radionuclide contamination and increases foil longevity from 2000 mAh to over 8000 mAh of proton beam exposure. Studies employing positron annihilation spectroscopy and TEM confirm the alloy's resilience against dislocation-induced degradation and predict extended operability in next-generation accelerators. As a precision-engineered foil, Havar plays a foundational role in improving FDG synthesis yields and sustaining high-current, low-contamination isotope production systems.