Physically Unclonable Surfaces Enabled by Cold Spray Deposition.

Area of Science:

• Materials Science
• Cryptography
• Surface Engineering

Background:

• Increasing prevalence of counterfeit components necessitates advanced authentication methods.
• Existing physically unclonable functions (PUFs) face challenges in high-throughput, cost-effective manufacturing and secure encoding.
• Need for robust traceability and tamper-evident solutions in critical industries.

Purpose of the Study:

• To develop an innovative, scalable, and cost-effective method for manufacturing physically unclonable functions (PUFs).
• To integrate algorithmic feature extraction and cryptographic encoding for secure part authentication.
• To address the limitations of current PUF fabrication techniques.

Main Methods:

• Utilized cold spray (CS) particle deposition to create unique luminescent patterns on an aluminum substrate using metal and fluorescent microparticles.
• Employed UV light exposure to capture particle distribution, followed by image binarization and Voronoi analysis for feature extraction.
• Encrypted extracted features using the SHA-256 algorithm to generate a secure certification key for authentication.

Main Results:

• Demonstrated high-throughput and scalable production of PUFs via the CS process.
• Confirmed the uniqueness and robustness of the generated luminescent patterns.
• Validated the effectiveness of the SHA-256 encrypted certification key for reliable part authentication.
• Showcased PUF reliability under environmental stressors like thermal cycling and chemical exposure.

Conclusions:

• The proposed cold spray-based PUF manufacturing method is effective, scalable, and cost-efficient.
• This approach provides a robust solution for secure part authentication and traceability.
• The technology has strong potential for tamper-evident solutions against counterfeiting in aerospace, defense, and advanced manufacturing.