Radiation-Resistant Ti/BN Coatings: Insights From 171 Days Exposure to Space Radiation and Atomic Oxygen in Low Orbit

Abhijith Kunneparambil Sukumaran; Sara Rengifo; William Scott; Annette Gray; Miria Finckenor; Rony Thomas Murickan; Justin McElderry; Matthew Mazurkivich; Michael Renfro; Sang-Hyon Chu; Cheol Park; Anna Wu; Yifei Fu; Sudipta Seal; Arvind Agarwal

NASA NTRS · 20260007753

Radiation-Resistant Ti/BN Coatings: Insights From 171 Days Exposure to Space Radiation and Atomic Oxygen in Low Orbit

Abhijith Kunneparambil Sukumaran·Sara Rengifo·William Scott·Annette Gray·Miria Finckenor·Rony Thomas Murickan·Justin McElderry·Matthew Mazurkivich·Michael Renfro·Sang-Hyon Chu·Cheol Park·Anna Wu·Yifei Fu·Sudipta Seal·Arvind Agarwal

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Abstract

Atmospheric Plasma Spray (APS) and Vacuum Plasma Spray (VPS) techniques were used to develop Ti/2 vol.% hBN coatings, for extreme space environments and tested aboard the International Space Station as part of the MISSE-17 (Materials International Space Station Experiments) program. The coatings were exposed to atomic oxygen, space radiation, and low-orbit thermal cycling. VPS coatings showed a 56% increase in microhardness, a 26% rise in elastic modulus, minimal porosity and crack density changes compared to APS coatings. The change in mechanical properties is attributed to the formation of TiO, TiO₂ and TiN from nitrogen retention, alongside radiation-induced dislocations, which enhanced surface hardening. The oxidation of titanium led to the formation of TiO and TiO₂, while boron nitride was retained and underwent transmutation in VPS coatings. XPS and EDS analyses confirmed the enhanced space-environment resistance of VPS coatings, making them ideal for long-term spacecraft protection in lunar and Martian conditions.

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Abhijith Kunneparambil Sukumaran, Sara Rengifo, William Scott, Annette Gray, Miria Finckenor, Rony Thomas Murickan, Justin McElderry, Matthew Mazurkivich, Michael Renfro, Sang-Hyon Chu, Cheol Park, Anna Wu, Yifei Fu, Sudipta Seal, Arvind Agarwal. 2025-07-26. Radiation-Resistant Ti/BN Coatings: Insights From 171 Days Exposure to Space Radiation and Atomic Oxygen in Low Orbit. https://ntrs.nasa.gov/citations/20260007753

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