ASTM F138 Implant-Grade 316L Surgical Steel

Surgical-grade stainless steel refined for implant use — the industry workhorse

ASTM F138 is a vacuum-melted (316LVM) variant of 316L stainless steel specifically formulated for surgical implants. The vacuum melting process significantly reduces non-metallic inclusions, resulting in a cleaner, more homogeneous material with superior corrosion resistance. Unlike standard 316L steel used in cookware or construction, ASTM F138 is regulated for medical implant use and contains lower carbon content (max 0.030%) to prevent intergranular corrosion. While it does contain nickel (12-14%), the nickel is tightly bound within the austenitic crystal structure, meaning it does not leach into the skin under normal conditions.

Biocompatibility

ISO 10993-1 certified for medical device biocompatibility. Used in bone screws, temporary fixation devices, and orthodontic brackets.

Nickel Content

12–14% nickel — bound within austenitic structure, minimal ion release. Not recommended for known nickel allergies.

Durability

Tensile strength 485–620 MPa. Excellent corrosion resistance in chloride environments. Maintains mirror polish for years.

Suitable For

• Healed piercings
• Budget-conscious quality
• Body jewelry with complex machining
• Threaded styles and intricate designs

Available Finishes

• Mirror Polish Silver
• PVD Gold
• PVD Rose Gold
• PVD Black

Care Instructions

• Wipe with soft microfiber cloth
• Avoid chlorine and salt water immersion
• PVD coatings require gentle handling