Removal of an island from a laser cut article

A method for removing an island from a refractory metal article, the method comprising:

• providing a refractory metal workpiece having an outer surface and an inner surface;
• laser cutting the refractory metal workpiece substantially continuously along a laser cut line that extends from the outer surface to the inner surface in a single pass to produce a laser cut refractory metal article that includes a plurality of laser cuts and one or more islands remaining between the laser cuts;
• and
• treating the laser cut refractory metal article to remove the one or more islands therefrom, the treating comprising:
• disposing the laser cut refractory metal article in a chemical etching solution that includes hydrofluoric acid (HF) and nitric acid (HNO3) for a period of time sufficient to remove the one or more islands therefrom so as to form an implantable device.

A method for removing an island from an implantable article, the method comprising:

• providing a tubular a tantalum alloy workpiece having an outer surface and an inner surface;
• laser cutting the tubular a tantalum alloy workpiece substantially continuously along a patterned laser cut line that extends from the outer surface to the inner surface to produce a laser cut stent that includes a patterned plurality of laser cut struts and one or more islands remaining between the laser cut struts, wherein the laser cut struts have a cross-sectional dimension of about 40 μm to about 120 μm;
• and
• treating the laser cut stent to remove the one or more islands therefrom, the treating comprising:
• disposing the laser cut stent in a chemical etching solution that includes hydrofluoric acid (HF) and nitric acid (HNO3);
• heating the laser cut stent in the chemical etching solution to a temperature in a range from about 40° C. to about 70° C.;
• sonicating the laser cut stent in the chemical etching solution using an ultrasonic apparatus;
• and
• treating the laser cut stent in the chemical etching solution under heating and sonication for a period of time sufficient to remove the one or more islands therefrom so as to form an implantable stent.

A method of manufacturing an implantable article, comprising

• providing a first refractory metal workpiece having an outer surface and an inner surface, the first refractory metal workpiece being made from a material selected from the group consisting of tantalum, niobium, tungsten, zirconium, molybdenum, and alloys thereof;
• laser cutting the first refractory metal workpiece in a single pass using a picosecond laser apparatus substantially continuously along a patterned laser cut line that extends from the outer surface to the inner surface to form a laser cut stent that includes a patterned plurality of laser cut struts and one or more islands remaining between the laser cut struts, wherein the laser cut struts have a cross-sectional dimension of about 40 μm to about 120 μm;
• treating the laser cut stent for a period of time sufficient to remove the one or more islands therefrom, the treating comprising:
• disposing the laser cut stent in a chemical etching solution that includes hydrofluoric acid (HF) and nitric acid (HNO3);
• heating the laser cut stent in the chemical etching solution to a temperature in a range from about 40° C. to about 70° C.;
• sonicating the laser cut stent in the chemical etching solution using an ultrasonic apparatus;
• wherein the treating does not include use of a mask capable of defining a plurality of struts and a plurality of islands remaining between the struts;
• electropolishing the laser cut metal stent in an electropolishing solution;
• and
• heat treating the laser cut refractory metal stent so as to form an implantable stent.