Titanium standards: why not G23?

*En Español*
Esteemed Colleagues:

I wanted to offer clarification for your jewelry materials, since this is one of my areas of expertise, so that you may give your customers the best information.

I noticed that many of you mention ASTM standards B863, B348 and G23 for your materials.

Please stop.

I’ve looked into ASTM F136, and ASTM B348 GR 23 standards.

While both are 6AL-4V ELI, ASTM F136 is the specification for the alloy to be used for surgical implants.

ASTM B348 GRADE 23 is not an implant grade of titanium and is not a substitute for ASTM F136.

-official representative of Titanium Industries

Grade 23 and the ASTM B series standards are not specific descriptions of materials for contact with the human body, rather they are wide designations for commercial, industrial and engineering purposes.

For human body contact as surgical implants or body jewelry, you’ll want your Titanium stock certified from your raw materials supplier to F136 or F67, and finish the products according to F2791 and F86. This will be to your advantage, and for your customers.

I strongly suggest that you do not refer to Ti as G23, because it is too vague, the more specific F136 standard is what it should meet the for the purpose of body jewelry. Other jewelers often use that terminology in a vague and misleading manner.

Titanium!As an analogy:

B863 or B348 would describe the country : G23 would describe the state : F136 or F67 would describe the city : F2791 would describe the measurement of the surface elevations of the terrain : F86 would describe how to clean that surface

Make sure that you check your raw materials for compliance to these standards. Your Ti material supplier should provide you with references of the standards that your stock meets upon request.

I will be pleased to help you with more details to get this perfected, since from what I’ve read, most of you really seem to want to make good jewelry.

Question: Does ASTM F136 always equate to Ti6Al4VELI? [edited for precision]

I understand that grade 23 or grade 5 or any grade is not the same as ASTM-F136. Yet I am wondering does F136 apply only to titanium with a specific amount of aluminum and vanadium. I assume it would for sure have extra low interstitial impurities. Does F136 always equate to Ti6Al4VELI, or is that term only as relevant to me as what “grade” the titanium is? I did read your article and I do understand the grade is meaningless but I wasn’t sure if knowing the parts V and Al were also meaningless.

— Julie Taylor, Skindecision

Answer: ASTM F136 is a refined version of Grade 23 Ti6Al4V ELI.

The ASTM F specifications for surgical implant materials are the only meaningful thing to discuss when it comes to body jewelry. F136 and F67 are the only two currently in large scale jewelry production. Take a look at the above links for the exact ASTM recipe. Grade and the general material descriptions are meaningless to us when we need to specify a safe biomaterial.

The ASTM F136 standard is a recipe, it tells us how to make the alloy, then how to validate the results with the proper tests. An independent lab can then offer a certificate of tests for material source, so that anyone who request that material can have proof that it is safe.

I find that it is much easier to understand if you think of Ti as the wax that makes a honeycomb, as it forms a hexagonal crystal structure, with plenty of other things where the honey would be that are removed when the metal is refined. The 6% Al Oxide and 4% V Oxide are ceramics that are added to fill the gaps left in the structure for durability. Any impurities that remain would cause biological incompatibility, so ELI means Extra Low Impurities in the interstice. Basically, we remove the honey, fill the spaces with ceramic, and should be left with a strong geometric structure without any dirty leftover pollen or sugar crystals.

Glad to help clarify! People tend to obfuscate the matter for the most part as a manner of marketing. It should be certified to the correct recipe, and all we have to know is the correct recipe was followed.

There are thousands of recipes to choose from when it comes to biomaterials for implant that ASTM technical committee F04 oversees.

33 thoughts on “Titanium standards: why not G23?”

  1. Funny you mention Wildcat. Upon multiple emails I never did get any further than that the Ti they sold was supposed to be “G23” and that it was “implant grade”. That was all they were (willing) to say on the subject.

    Even more, I’ve been questioning their extreme claims about their new “healium” and the mere fact they did not want to share anything about the nature of the material. Quite obviously, we’re talking about a antimicrobal polymer with a selfproclaimed “G23” ball-end, externally threaded. I’l keep my personal opiniom to a minimum – as I am still writing a little article – but I would be interested in your professional opinion of the use of such polymers for initial body piercing?

    Reply
    • Please include me in your correspondence with companies and I will help interpret the standards together with you.
      I have no problems with a company introducing a novel material that has been tested and proven safe for human implant, if they provide documentation that it meets appropriate standards.

      Reply
      • Thanks Brian, that would be great! I’ll contact you as soon as I get back from them (or atleast something more than “its a secret”). I do have some questions still, regarding antimicrobactal polymers and Ethylene Oxide.. more specifically concerning alkyl or acetyl linkers and alkylation. Could I contact you about that too?

        Reply
  2. I'm glad you've clarified this. I get phone calls from manufacturers constantly who claim G23 is good enough and really "implant-grade". It would be great if the APP could send notice to these vendors & manufacturers that they are giving fraudulent information.

    Reply
  3. ISO 5832-3:1996 would be the appropriate harmonized normative. ASTM F136 is an internationally applicable standard to demand when ordering raw materials. There are a number of other related standards under the ISO 5832 heading.

    Abstract:

    Specifies the characteristics of, and corresponding test methods for, the wrought titanium alloy known as titanium 6-aluminium 4-vanadium alloy (Ti 6-Al 4-V alloy) for use in the manufacture of surgical implants.

    http://www.iso.org/iso/iso_catalogue/catalogue_tc

    Reply
  4. thank you for the info. does it make sense if a jewelry company says that their titanium has a Nickel content that is less than 0.05% by mass
    does titanium have any nickel in it at all?

    Reply
    • The company is probably mentioning the lack of Nickel because the European regulations specify less than 0.05%, and have been revised to take into account Ni leaching into the system and the sensitization that can occur. Pure Ti is elemental and when refined should not have more than the slightest detectable amount of any other elements, with the exception of the tiniest amounts of dissolved gases such as Oxygen and Nitrogen.

      Reply
  5. 1) So are the European Titanium standards and quality same as in the USA?
    2) Would you recommend buying jewelry from Europe at all?

    They say in the website that the titanium alloy that they use is Ti 6AL4V

    Reply
    • 1) ASTM and ISO safety standards are international, with very few differences. It should be possible to get quality jewelry from EU suppliers, but you should not buy without proper documentation that the products are safe.
      2) I do not yet have such documentation from any company outside of the US, although it seems that companies such as Wildcat and Trust would be willing to provide it upon request.

      The Ti alloy that you mentioned the company using is not enough to assure safety, and it is vague and possibly misleading. The Ti6Al4V alloy is primarily used for engineering and aerospace, and must be highly refined through further processes and tested for purity to ensure that it meets ASTM F136 standard for surgical implant.

      Reply
  6. Note: We face similar issues with misleading steel standards, when companies claim industrial categories such as AISI 316L or SUS316L instead of specifically refined standards for surgical implant such as ASTM F138 or ISO 5832-1:1997 or ISO 5832-9:1992.
    * I strongly prefer jewelry materials that are entirely composed of non-toxic elements. Pure Ti ASTM F 67 over alloyed F 136, for example. I look forward to body jewelry manufacturers moving away from steel and choosing pure Ti or Ti alloyed with Nb Zr or Ta for attractive surface finish and true biocompatability rather than biotolerance.

    Reply
  7. Note: We face similar issues with misleading steel standards, when companies claim industrial categories such as AISI 316L or SUS316L instead of specifically refined standards for surgical implant such as ASTM F138 or ISO 5832-1:1997 or ISO 5832-9:1992.
    * I strongly prefer jewelry materials that are entirely composed of non-toxic elements. Pure Ti ASTM F 67 over alloyed F 136, for example. I look forward to body jewelry manufacturers moving away from steel and choosing pure Ti or Ti alloyed with Nb Zr or Ta for attractive surface finish and true biocompatability rather than biotolerance.

    Reply
    • Olá amigo! Obrigado!
      Olá amigo. O link 23 Grau que forneceu é para a categoria geral. Para cumprir a norma implante cirúrgico ou para a jóia do corpo, ele deve ser mais refinado e controlado para atender ASTM F136.
      [Hello my friend. The Grade 23 link you provided is for the broad category. To meet the surgical implant standard or for body jewelry, it must be more refined and controlled to meet ASTM F136.]

      Reply
  8. ASTM F136 and ASTM F67 are standards for human implant. Think of them each as a different recipe, with specifications for ingredients (chemistry), for how to mix (microstructure), also for how to cook (mechanical properties). By following the recipe, you get a predictable safe result, which can then be tested and validated to meet the ASTM standard. ASTM has started a program to track validation for suppliers at http://www.astm.org/suppliers

    Reply
  9. Umm does wildcat sell the proper titanium or doesn't it ?
    We talked about at last years bmx (you sterilised my circular barbells with the statim, enjoyed talking to you )
    I do a lot with the wildcat stuff, not that mutch with IS … have it but people dont want to pay for it(not enough people anyway)

    Reply
    • Only the materials under the scope of the ASTM F04.12 subcommittee on metallurgical materials that are specified for surgical implant should be considered, due to the testing performed which is required to qualify as an implant material. Using other engineering materials poses too many risks to contend with, beginning with loss of life and other major disadvantages due to unpredicted or predictable negative reactions in the human body.

      Reply
  10. Thanks for gathering and summarizing all that info! As a metallurgy and body mod aficionado I really appreciate! Do you know any jewellery manufacturers that use F 67 Ti?

    Reply
  11. I bought grade 23 for my daith piercing. What will happen to my piercing since I switched from surgical steel to the titanium grade 23?

    Reply
    • Commercially Pure titanium is not an alloy as those standards refer to. It has it’s own set of standard specifications under ASTM F67 for variations on purity which differ mostly in the dissolved gases.

      The APP initial body jewelry standards address this:

      “Titanium (Ti6Al4V ELI) that is ASTM F136 compliant or ISO 5832-3 compliant

      Titanium that is ASTM F67 compliant”

      Reply
  12. Wow I am so glad I have found you! I have fallen into being the only piercing studio in my city (that’s another story!) I have spent the last year trying to learn everything I can about the safest piercing materials to use on and sell to my clients. I live in Australia and have discovered a disturbing lack of information available, let alone quality jewellery. Wildcat. This is the most trusted wholesaler in Australia yet they sell acrylic jewellery and the titanium is unspecified. Is it your opinion that their titanium jewellery is unsafe? I would like to provide my clients with the safest jewellery I can afford. I have been relying heavily in Invictus body jewellery. What is your experience with the safety of their titanium please? Please advise on safest wholesalers I can buy from! Many many thanks.

    Reply

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