Methods of fabricating a refractory-metal article, and apparatuses for use in such methods
AssigneeAbbott Cardiovascular Systems Inc.
InventorsRainer Bregulla, Armin Stopper
Life of this patent
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Abstract
Embodiments of methods for fabricating refractory-metal articles (e.g., implantable medical devices), and honing and blasting apparatuses for use in such methods are disclosed. Methods for fabricating refractory-metal-containing articles include laser cutting in a vacuum environment and/or at least one mechanical or chemical finishing step configured to remove at least one region affected by the fabrication process (e.g., the laser cutting process) to provide a substantially defect-free surface finish.
Claims33
A method of laser cutting, comprising:
- disposing a first refractory-metal article in a chamber of a laser cutting apparatus;
- drawing a partial vacuum in the chamber having the first refractory-metal article disposed therein;
- and
- laser cutting the first refractory-metal article under the partial vacuum to form a second refractory-metal article.
The method of claim 9, wherein the first refractory-metal article exhibits at least one of a tungsten content of about 0.1 to about 15 weight percent, a zirconium content of about 0.1 to about 10 weight percent, or a niobium content of about 5 to about 25 weight percent.
A method for finishing a refractory-metal, comprising:
- providing a first refractory-metal article that includes one or more regions affected by at least one manufacturing process, the one or more regions including at least one of a heat-affected zone, dross, a slag, an oxide-rich zone, an island, a burr, or a score mark;
- and
- finishing the first refractory-metal article to remove the one or more regions therefrom affected by the at least one manufacturing process to form a finished second refractory-metal article.
A honing apparatus configured for honing a tantalum-based refractory metal implantable article in order to remove one or more regions therefrom affected by at least one manufacturing process, the one or more regions including at least one of a heat-affected zone, dross, a slag, an oxide-rich zone, an island, a burr, or a score mark, the honing apparatus comprising:
- an abrasive file that is dimensioned to be inserted into an interior passageway of the implantable article;
- a motor structure configured for gripping and rotating the abrasive file;
- an arrester configured for holding the file in a substantially straight orientation;
- and
- a roller positioned and configured to bias interior surfaces defining the interior passageway of the implantable article against the file.
A blasting apparatus configured for blasting an implantable, the blasting apparatus comprising:
- a support structure;
- at least one blasting nozzle mounted to the support structure, the blasting nozzle being configured to direct high-velocity abrasive particles from a source of said particles toward an implantable article;
- a roller assembly disposed on the support structure, the roller assembly being configured to cradle, position, and rotate the implantable article under the at least one blasting nozzle;
- and
- a plurality of biasing elements operatively coupled to the support structure and the roller assembly, the biasing elements being configured to provide a selected amount of compressive pressure to the implantable article disposed in between the rollers,
- wherein the blasting apparatus is configured for blasting an inner diameter surface and an outer diameter surface of the implantable article.
A method for manufacturing an implantable medical device, comprising:
- providing a first refractory-metal article, the first refractory-metal article including a material selected from the group consisting of tantalum, niobium, tungsten, and alloys thereof;
- disposing the first refractory-metal article in a chamber of a laser cutting apparatus;
- drawing a partial vacuum in the chamber having the first refractory-metal article disposed therein to a vacuum level of about 25 torr to about 10−12 torr in pressure such that hydrogen embrittlement does not occur in the first refractory-metal article during and/or after the laser cutting;
- laser cutting the first refractory-metal article under the partial vacuum to form a second refractory-metal article;
- mechanically and/or chemically finishing the second refractory-metal article to remove one or more regions therefrom affected by at least one manufacturing process using at least one of honing, blasting, thermal blasting, chemically etching, or electropolishing,
- the one or more regions affected by the at least one manufacturing process including at least one of a heat-affected zone, a slag, islands, burrs, or score marks;
- and
- annealing the mechanically and/or chemically finished second refractory-metal article to yield the implantable medical device.
Dependencies are inferred from the claim text.