Abstract: A radiopaque tube for use as a medical catheter is provided. The tube is preferably formed about a wire mandrel which is subsequently removed to form the lumen of the tube. The tube includes an inner wall layer made from a polymer resin defining the lumen. A spiral wound reinforcement layer of a radiopaque material is wound about the inner wall layer. The spiral wound layer can comprise flat wire or a multiple strands wound about parallel to each other. A polymer resin outer wall layer is laid over said spiral wound radiopaque layer so that the radiopaque layer is embedded between the inner wall layer and the outer surface of the outer wall layer.

Abstract: A method for processing a copper alloy wherein the alloy comprises from 0.2-1.0% beryllium, 1.4-2.2% nickel or cobalt and remainder copper. Said method comprising one or more processing steps and characterized in that said steps conclude with cold working the alloy to an area reduction of at least 99% followed by a batch annealing at a temperature of 750.degree.-950.degree. F. for a period of 1-4 hours.