Almost any of the implantable metals should do.

Obviously not looking for flexibility or non-kink when bending.

What's wrong with SS? I've helped use SS wire when fixing chest cavity surgery. (Tying ribs together).

What is used as to "tie" jawbones and other facial reconstruction work?

What is already used for needles? (some stay in place for weeks.)

They are using SS 316 L wall thickness 0.5 mm ( for 10 gauge tube )

Its too much for me .looking for material wich will allow to manufacture tube with wall thickness 0.1-0.2 mm and same rigidity /stifness like SS 10 gauge

At this point consider titanium alloy ( cannot find manufacturer of this wall thickness though)

Might be fiber glass /carbon composite tubes (not sure if they are blood compatible ,and again cannot find manufacturer of ultrathin wall (0.1-0.2 mm )

http://www.thomasnet.com/products/tubing-thin-wall-seamless-88677885-1.html

I would like to suggest extruded teflon. The long chemical chain should provide the required stiffness and strength, but- if a test section seems unstable, you can use a fiberglass core in the extrusion.

The only material in contact with blood would be the teflon.

its very intresting idea .cam you please suggest me couple manufacturers who would be able to do it? thnx

Look up http://www.frontier-lab.com/product/catalogue/UA.pdf which makes SS capilary tubes. May be look for capillary tubes http://www.bd.com/vacutainer/products/capillary/

Glass.

You have asked for stiffness with no mention of end use. So will glass do the job?

If you are serious about wanting a tube with a thin wall and higher rigidity than stainless steel, your only option is to investigate materials with higher elastic modulus than stainless steel. This eliminates plastics, glass, most metals, and leaves materials like beryllium, carbides, and very few others.

Stainless is hard to match for stiffness. Cobalt chrome is a possibility, and is stronger as well. Titanium is about half as stiff. Plastics are not even close, although carbon fiber reinforced plastics can be as stiff as stainless.

Carbon fiber reinforced carbon?

General info on implantable metals.

It will be very difficult to find something that will be as stiff as the 10 gauge stainless tube, given the smaller OD and thinner wall. Even at the same diameters, you'd need a material with more than twice the stiffness of stainless. (10 g = .2mm wall. Proposed, at 2.8 mm id ~ .1mm wall.) The reduction in OD would require an additional 45% higher modulus to give equal structural stiffness.

Have you looked at Viton DuPont fluoropolymers or Solvay fluoroelastomers?

Viton has certainly been used for replacing veins and arteries.