There is disclosed medical devices, such as stents, guidewires and embolic filters, comprising a binary alloy of titanium and one binary element selected from platinum, palladium, rhodium, and gold. There is also disclosed a radiopaque marker comprising the disclosed binary alloy, as well as medical devices having the radiopaque marker attached thereto. Methods of attaching the radiopaque marker to the medical devices, such as by welding, are also disclosure also disclosed.