Guide wires and catheters made from a functionally graded alloy comprising
3-10 weight % Al and 5-20 weight % Mn, the balance being substantially Cu and inevitable
impurities. The functionally graded alloy is produced by forming the copper-based
alloy, maintaining it at a temperature of at least 500 C. and rapidly cooling
it, and then subjecting the alloy to an aging treatment by a gradient temperature heater.
