Titan G23 vs. ASTM F-136 – what is the difference?

In short: There is usually no real difference in the material itself—only in the name.

Titanium G23

• Designation for the alloy Ti-6Al-4V ELI
• "ELI" = Extra Low Interstitials (particularly pure titanium)
• Highly biocompatible
• Frequently used for implants and high-quality piercing jewelry
• Nickel-free and corrosion-resistant

ASTM F-136

• ASTM F-136 is not an alloy, but a standard.
• This standard defines the exact requirements for medical implant titanium (chemical composition, purity, mechanical properties).
• The material is also Ti-6Al-4V ELI.

The real difference

• G23 describes the titanium alloy
• ASTM F-136 describes the quality and testing standard

Conclusion

In most cases, manufacturers mean practically the same material when they refer to "titanium G23" and "ASTM F-136." The difference is that ASTM F-136 additionally guarantees that the titanium is medically tested and complies with standards.