Which 4XX grade is best?

By spots

Date 06-15-2009 22:15

What is your application?

By sazid98 (*)

Date 06-15-2009 22:24

Its main application will be in medical implantation. so biocompatibility of the parts are important. i am trying to weld grade 2 Ti with stainless steel

By G.S.Crisi (****)

Date 06-15-2009 23:40

In my opinion, if the final use will be a medical implantation, i.e., something that will be lodged in a human body, the main point isn't what material you prefer, but what's the correct material recommended by doctors. Have you checked that?
Giovanni S. Crisi
Sao Paulo - Brazil

By Lawrence (*****)

Date 06-16-2009 06:06

Professor Crisi is right.. The decision your making is far beyond the scope of this little chat room.

http://www.stellite.com/IndustrialApplications/MotionSpecialIndustries/MedicalImplantsAncillaryInstrumentation/tabid/258/Default.aspx

http://www.sme.org/cgi-bin/find-articles.pl?&ME07ART37&ME&20070509&&SME&

http://www.mdtmag.com/scripts/ShowPR.asp?PUBCODE=046&ACCT=0006106&ISSUE=0501&RELTYPE=PR&PRODCODE=0390&PRODLETT=A&CommonCount=0

By 803056

Date 06-17-2009 03:51

Both Martensitic and Ferritic stainless steels are included in the AISI 4XX series of stainless steels. Which type is best for medical implants?

What kind of welding question is that? You need to talk to someone that is an expert in the field of medical implants and I somehow doubt many of them frequent this forum. Heck, we're welding geeks, not medical specialists! ;)

There is one person I know that is a medical doctor that just loves to weld. He is a member of our Connecticut Section of AWS. There is an outside chance he might look in on our little forum on occasion. Maybe you'll get lucky and he'll spot this inquiry. It would be a long shot! I don't have his e-mail address, so I can't forward this inquiry to him. Sorry.

My advice is to follow up on Lawrence's suggested web sites. Lawrence gives some very good advice on a wide range of welding topics.

Best regards - Al

By sazid98 (*)

Date 06-17-2009 17:15

Thank you all for your valuable suggestions. My work is still in the research stage. We all know that members 3XX series are more suitable for welding.

But some recent studies have raised questions against the biocompatibility of Ni. So we have choose 4XX series as there is almost no Ni in these series. But it is also fact that weldability of 4XX series is not as good as 3XX series. Regarding bio compatibility i believe it is sae to say that 4XX series is more bio compatible than 3XX. in the literature so far i have found they have suggested the above mentioned members from 4XX. so from the real hands on expert on welding i am expecting some kind of suggestion regarding the weldability among these few choices of 4XX so that i will be able to perform laser welding on them successfully.

thak you again

regards

Sazid

By 803056

Date 06-17-2009 20:34

ASM has some literature on alloys to be used for implants and they also have information on welding some of the alloys involved. It would be worth your time to check out their bookstore.

Best regards - Al

By MMyers

Date 06-18-2009 21:59

I would also suggest checking out Lippold and Kodecki's book "Welding Metallurgy and Weldability of Stainless Steels". There are sections devoted to ferritic and martensitic stainlesses and common welding related issues with these families of steels.

By ssbn727 (*****)

Date 06-18-2009 06:56 Edited 06-18-2009 07:09

Now hold on there partner!!! Did you just say that you're trying to weld grade 2 Ti with a grade of stainless steel???

If you're talking about medical implantation, and implanting into an environment where the possibility of enhancing the corrosion potential where the two different metals are fused together without any control of dilution as a matter of concern, and not to mention the difference in noble #'s between whatever grade of stainless steel when mixed together with Ti - just makes a bad recipe that much closer to a recipe for disaster for the poor soul who will have the unfortunate luck of having this device fail inside of them... Are you really willing to risk such liability without considering at the very least these and mant more risk factor that MUST be considered when designing & manufacturing such critical device where the only ethical goal is to make it as safe as humanly possible???

I echo what Lawrence and Al suggest... Get in contact with some folks that are experts in this speciality, and digest as much reference data out there because if you do not, you will step on a landmine that will not only kill you in endless litigation if you even get it approved beforehand... It will almost certainly kill someone innocent, and as a consequence, cause more harm and litigation
to any one else associated with the defective product.

I would strongly suggest that you get in touch with TIMET as they are some of the best folks out there to advise you when it comes to successfully fusing together Grade 2 Ti, and I believe they know a thing or two when it comes to medical applications such as implanted devices. Titanium Industries may also be helpful as well as RTI international.
Las but not least, visit the corrosion doctor's web site as they will school you on the fundamentals regarding certain factors involving corrosion control because after all, the human body is at least ninety plus per cent water!!!!! CAPECHE??? Yes INDEED!!! OXIDATION DOES HAPPEN INSIDE ALL OF US ONE WAY OR ANOTHER!!!! :) :) :)

If you want me to paste the links - forget that!!! You're responsible to do the appropriate research so, Good Hunting!!! :) :) :) :) :)

Respectfully,
Henry

By jsdwelder (***)

Date 06-18-2009 15:43

I'd use 6010 !!!!