Since 2000, the NETL has cooperated with a major medical devices corporation through a Cooperative Research and Development Agreement to develop a new series of medical alloys that will enhance the performance of medical devices by increasing their fluorescent radiopacity (making them more visible by x-ray). NETL scientists developed and then perfected the processing steps to make the alloy and turn it into usable ingot, plate, sheet, and foil products.

One example of a use for this alloy is in the development of coronary stents. Balloon expandable, coronary stents are small expandable tubular cages used to repair damaged arteries. Stents are placed through non-invasive procedures inside diseased arteries that have been identified as areas where blood flow is restricted. To facilitate this low risk, non-invasive procedure, coronary stents are compressed to a minimum diameter and mounted on a balloon catheter which is then inserted through an artery until it reaches the target location where it is expanded by pressurizing the balloon catheter. This type of catheter often uses high density marker bands to increase the radiographic visibility of deployment system, enabling accurate placement. Once deployment system with its marker bands is removed, the stent may not be detected by x-ray because of its poor radiopacity. This represents a potential problem if the stent needs further dilatation.

The cooperator decided that the best method to increase the radiopacity of its stents was to fabricate them from a more radiopaque alloy. Cooperator scientists contacted the U. S. Department of Energy's NETL's Albany site in June of 2000 to help develop a suitably radiopaque alloy for their stents. Over the past four years, a joint research program to develop new alloys for these devices resulted in developing a series of stainless steel alloys modified by the introduction of proprietary alloying constituents to increase radiopacity. A number of different elements were tried as candidates for alloy additions before the present set of constituents were determined to be the best candidate. NETL scientists and engineers were active in all facets of the alloy development and worked with several of the cooperator's subcontractors to develop the alloy formulation. NETL was responsible for the characterization of the chemical and physical properties of the alloys along with extensive microstructural analysis and corrosion studies. The new alloys exhibit different mechanical properties than that of the stainless steel alloy they will replace. New parameters had to be developed for melting and fabricating these alloys.

Primarily, NETL personnel developed the process to melt and cast these new alloys and fabricate them into thin sheet when needed and have concentrated on an effort to increase the yield from melting to product. The cooperator's scientists and engineers then developed the final, proprietary heat treating steps with input from NETL scientists; and then NETL assisted the cooperator in developing the process to perform the difficult task of rolling this alloy from sheet to foil before fabricating into devices. During the prototype to marketing phase, NETL scientists served as consultants to assist the cooperator in certifying a commercial firm to produce the alloy for the production phase of the new product line. The cooperator has decided to design several product lines around the newly developed alloys. The commercial products will be introduced in 2006 and 2007 with estimated yearly sales in excess of one billion dollars.