Coating & Finishing of Titanium for Biomedical

A. Dear Mr. Landry:

Nitrogen or carbon ion implantation has been used with success to address friction and wear issues on Ti alloy orthopedic implants.

Regards,

A. Dear Michael:

I am working with the Nanotechnology Laboratory at The University of Nebraska Medical Center. Nitrogen and Oxygen cannot be used, we have addressed this problem.

Regards,

----
Ed. note: Readers, this forum is for public info exchange. Please share anything you feel free to, but don't hint towards private contact: it disenfranchises the other readers who get to hear only half the story, and it's unfair to our supporting advertisers :-)

A. Sir Michael,
My application is on Titanium 6-4 also, but in a different industry. I suggest that you consider Tiodize II. They will furnish test data.

----
Ed. note: We thank John for this helpful posting from 2009 but times have changed and we can't post vendor/sourcing suggestions anymore ( huh? why?)

A. Anodizing of titanium provides good protection, but it is not very flexible. Conversion coatings would be much thinner than your requirement and less effective. Have you considered powder coating?

A. Jon,

Perhaps I missed something, but I was thinking conversion coating more along the lines of SAE AMS2486 Conversion Coating of Titanium Alloys Fluoride-Phosphate Type than a coating for biocompatibility. Obviously coatings suitable for titanium implants must meet a stringent set of requirements. Maybe I am being naive, but I cringe at the thought of a person working on a biomedical application asking a generic question over the internet.

The coating is not for biomedical. I would also cringe if this question were for that. It is an industrial application. I have contacted Tiodize about the anodizing and have sent them a sample. I will also be checking into the Timadize. I thank you all for your help and will let you know if I need more help.

the light side

... and the score at the end of eight: Cringers 2, Wincers 1. Ted Mooney, P.E. Striving to live Aloha finishing.com - Pine Beach, New Jersey 2003

A. Nitric/HF will probably brighten titanium. To dull the surface use a mixture of 8 oz/gal Potassium Hydroxide + 5% Hydrogen peroxide at room temperature. This will require 1 to 4 hours to produce a dull etched finish.

A. I have not seen that problem after etching with KOH/H2O2 mixture. Will a simple high pressure remove it?

A. You need chemical vapour deposition (CVD) or a similar process.

A. Dear sir,

I'd like to share some points on TiN coatings on medical equipments. TiN coating or titanium nitride coating is mainly done on cutting tools like HSS material, carbide material, etc., to improve the cutting tool life and injection mould life.in machine tools.
There are 2 types of TiN coating: physical vapor deposition (PVD) process and CVD process. If you can give more on your application requirements I can share with you more details.
With warm regards,

A. There are several ways to activate the surface of titanium implants to create better adhesion to the bones. One of the methods is called "volcano" and can be obtained by creating special porous oxide layer on the surface. There are other proprietary methods to obtain similar surfaces.

adv.
Contact us for more information.

A. Hi, Ved.

The "coloring" on titanium is not a pigment or patina, it's a clear coating of titanium dioxide that is so thin that it gives the appearance of colors by the same diffraction mechanism as carnival glass or the rainbow sheen of oil on a water puddle. Various colors are obtained by varying the concentration, time, and temperature to build films of different thicknesses. So the coloring of titanium is easy in principle, and tens of thousands of amateur jewelry designers do it, using electrolytes ranging from coca-cola to TSP, and voltages ranging up to 240 V (dangerous, and requires isolation transformer).

But medical implants are not baubles and trinkets! They require biocompatibility, anatase not rutile coatings (thanks, Ling Hao; see letter 7068), and rigorous quality control. You may want to license this technology from a company like Russamer Lab [a finishing.com supporting advertiser], because implants are a serious matter and not a good practice opportunity. Best of luck.

Regards,

! That was one of the scariest questions I've seen on this site. Marc Green anodizer - Boise, Idaho August 22, 2011

A. Emily,

You can purchase the article from http://www.sciencedirect.com/science/article/pii/S1751616107000409 online.

Hi Rob,

adv.
Please contact me directly. We provide consultations on titanium surface treatments and surface preparation. There are several methods on how safely, without hydrogen saturation, to make the titanium surface rough.

A. It appears we are talking about two or three different processes - roughening the surface, increasing the wetability, and developing a porous oxide layer. The pictures presented by Anna Berkovich showing the "volcano" appear to be a thick porous oxide layer deposited by plasma electrolytic oxidation process. The other process is chemical etching which provides a rough surface with a thin unavoidable oxide layer. Both increase the surface wettability.

Rob van den Dungen talks of applying "several coatings" but does not specify the purpose or type of coatings. Emily Smith talks of spinal screws while Baldwin Goodell talks of osseointegration. The two may not be different. But 'biocompatibility' sometimes refers to undesirable bacterial growth on implants.
I hope it may not be out of place to add to the confusion!

Wettability can be achieved by first degreasing and then a 'simple' plasma (argon/air/oxygen) treatment. This is an environmentally friendly physical process. No significant etching is involved in this.
One can excite an electric arc on titanium surface in vacuum so that the arc moves all over the surface randomly removing titanium atoms and creating micro and nano sized craters on the surface. This is one of the PVD techniques to deposit hard coatings like TiN. This gives a clean etched surface. I don't know if anyone has used this physical technique for etching. It is worth trying.

A. Hi H.R.

The image of the surface in my previous posts does not refer to this question. The highly developed surface that is attached to my current posting is done by electrochemically etching the surface for future 'Brushete" coating for better ossiointegration. Can be also used for titanium surface preparation before plating.