Patent ID: 8241441

Claim:
A process for thermally treating and coloring a plurality of curved suture needles to colorize and enhance the stiffness and yield moment of the curved suture needles, the process comprising the steps of: a) conveying the plurality of curved suture needles comprised of a tungsten alloy from a source of curved suture needles to a receiver; b) heating the plurality of curved suture needles to a temperature ranging from about 350 to about 1900° C. for about 1 second to about 5 minutes as the plurality of curved suture needles pass between the source of curved suture needles to the receiver; c) providing a gas mixture containing a fractional concentration of oxygen; and d) coloring surfaces of the plurality of curved suture needles as the plurality of suture needles pass through the gas mixture containing a fractional concentration of oxygen as the plurality of suture needles are heated.