Abstract: A wire cable construct including a plurality of strands each made of a plurality of wire filaments, the strands and wire filaments arranged in a 37×7 configuration of 37 strands of 7 wire filaments each, with the strands arranged in four layers including a first, central layer of a single strand, a second layer of six strands, a third layer of twelve strands and a fourth, outermost layer of eighteen strands. The cable may have a small diameter for use in medical device applications, and the strand and wire element configuration allows the cable to carry high axial loads, minimizes bending stress when the cable is routed around a tight turn such as a small pulley, and minimizes torsion in the cable due to axial loading.

Abstract: A magnesium alloy contains a small amount of lithium, zinc, calcium, and manganese. For example, the magnesium alloy may include between 1-5 wt. % lithium, between 0.2-2.0 wt. % zinc, between 0.1-0.5 wt. % calcium, and between 0.1-0.8 wt. % manganese. These alloying elements are all nutrient elements, such that the present alloy can be safely broken down in vivo, then absorbed and/or expelled from the body. Li, Zn, Ca and Mn each contribute to solid-solution strengthening of the alloy. Ca also acts as a grain refiner, while Zn and Ca both form strengthening and corrosion-controlling intermetallic compounds. Optionally, the alloy may also include a small amount of yttrium for added strength and corrosion resistance.

Abstract: A swaged fitting can be fixed to a wire rope while simultaneously providing a desired shape and size, thereby avoiding the need for subsequent material removal. In one application, the swaged fitting is fixed to the wire rope by a forging operation such that the fitting is securely fixed provides a straight-sided construct once fixed to the wire rope. After the forging operation and without further material removal, the straight sides of the finished fitting are generally parallel to the longitudinal axis of the wire rope, while the end surfaces of the fitting are generally perpendicular to this longitudinal axis. This arrangement provides a strong and effective force-transfer interface for, e.g., end-effectors in medical devices.

Abstract: Multi-filament microcables are used in place of the traditional monofilament wires as the constituent elements of a woven or braided band. This enhances the function and manufacturability of such bands for various applications, such as orthopaedic applications including sternotomy closures.

Abstract: A nickel-titanium alloy is made to be wholly or substantially free of titanium-rich oxide inclusions by including yttrium in an amount up to 0.15 wt. %, with the balance of the alloy being nickel and titanium in approximately equal proportion. For example, a NiTiY alloy may have a composition including, in weight percent based on total alloy weight: between 50 and 60 wt. % nickel; between 40 and 50 wt. % titanium; and between 0.01 and 0.15 wt. % yttrium. The resulting alloy is capable of being drawn into various forms, e.g., fine medical-grade wire, without exhibiting an unacceptable tendency to develop surface defects or to fracture or crack during cold drawing or forging. The resulting final forms exhibit favorable fatigue strength and fatigue-resistant characteristics.

Abstract: A group of substantially nickel-free beta-titanium alloys have shape memory and super-elastic properties suitable for, e.g., medical device applications. In particular, the present disclosure provides a titanium-based group of alloys including 16-20 at. % of hafnium, zirconium or a mixture thereof, 8-17 at. % niobium, and 0.25-6 at. % tin. This alloy group exhibits recoverable strains of at least 3.5% after axial, bending or torsional deformation. In some instances, the alloys have a capability to recover of more than 5% deformation strain. Niobium and tin are provided in the alloy to control beta phase stability, which enhances the ability of the materials to exhibit shape memory or super-elastic properties at a desired application temperature (e.g., body temperature). Hafnium and/or zirconium may be interchangeably added to increase the radiopacity of the material, and also contribute to the superelasticity of the material.

Abstract: A wire cable construct including a plurality of strands each made of a plurality of wire filaments, the strands and wire filaments arranged in a 37×7 configuration of 37 strands of 7 wire filaments each, with the strands arranged in four layers including a first, central layer of a single strand, a second layer of six strands, a third layer of twelve strands and a fourth, outermost layer of eighteen strands. The cable may have a small diameter for use in medical device applications, and the strand and wire element configuration allows the cable to carry high axial loads, minimizes bending stress when the cable is routed around a tight turn such as a small pulley, and minimizes torsion in the cable due to axial loading.

Abstract: A nickel -titanium alloy is made to be wholly or substantially free of titanium-rich oxide inclusions by including yttrium in an amount up to 0.15 wt. %, with the balance of the alloy being nickel and titanium in approximately equal proportion. For example, a NiTiY alloy may have a composition including, in weight percent based on total alloy weight: between 50 and 60 wt. % nickel; between 40 and 50 wt. % titanium; and between 0.01 and 0.15 wt. % yttrium. The resulting alloy is capable of being drawn into various forms, e.g., fine medical-grade wire, without exhibiting an unacceptable tendency to develop surface defects or to fracture or crack during cold drawing or forging. The resulting final forms exhibit favorable fatigue strength and fatigue-resistant characteristics.

Abstract: Ti—Nb—Hf/Zr—(Cr) alloy shape-memory wires are provided which are suitable for use in medical devices and actuators, and methods for manufacturing such wires are provided. The present shape-memory Ti—Nb—Hf/Zr—(Cr) alloy is a superelastic wire material particularly suited for in vivo applications. For example, the present Ti—Nb—Hf/Zr—(Cr) alloy wire is radiopaque, thereby enabling surgical use of a monolithic, shape-memory alloy wire while preserving the ability to monitor the in vivo location of the wire through X-ray or other radiation-based imaging systems. In addition, the present Ti—Nb—Hf/Zr—(Cr) alloy can be manufactured to exhibit shape-memory alloy material properties without the use of nickel as an alloy constituent, thereby accommodating nickel-sensitive patients. The present Ti—Nb—Hf/Zr—(Cr) alloy can also be processed to exhibit a martensite/austenite transformation temperature near body-temperature, i.e., 37° C., so that shape-memory effects can be utilized to accomplish work in vivo.

Abstract: Multi-filament microcables are used in place of the traditional monofilament wires as the constituent elements of a woven or braided band. This enhances the function and manufacturability of such bands for various applications, such as orthopaedic applications including sternotomy closures.

Abstract: A spool for use in a wire braiding machine, for example, which has a “bi-tapered” design including a central cylindrical section and a pair of tapered (e.g., frusto-conical or parabolic) flanges having surfaces that slope inwardly toward the cylindrical section. In this manner, the spool provides a progressively widening wire fill area, as measured along a direction parallel to the rotational axis of the bobbin, as the wound wire advances progressively radially outwardly from the cylindrical section. This widening wire fill area aids in preventing the formation, propagation and buildup of wire winding defects, such that the wire is more likely to unspool or pay-out from the spool without losing tension, snagging or breaking.

Abstract: A bioabsorbable wire material includes manganese (Mn) and iron (Fe). One or more additional constituent materials (X) are added to control corrosion in an in vivo environment and, in particular, to prevent and/or substantially reduce the potential for pitting corrosion. For example, the (X) element in the Fe—Mn—X system may include nitrogen (N), molybdenum (Mo) or chromium (Cr), or a combination of these. This promotes controlled degradation of the wire material, such that a high percentage loss of material the overall material mass and volume may occur without fracture of the wire material into multiple wire fragments. In some embodiments, the wire material may have retained cold work for enhanced strength, such as for medical applications. In some applications, the wire material may be a fine wire suitable for use in resorbable in vivo structures such as stents.

Abstract: A composite wire product includes a biodegradable parent material which forms the bulk of the cross-sectional area of the wire, and a central fiber or filament of a slower-degrading or non-biodegradable material runs throughout the length of the wire. This central filament promotes the mechanical integrity of an intraluminal appliance or other medical device made from the wire product throughout the biodegradation process by preventing non-absorbed parent material from dislodging from the central filament. Thus, the present wire design enables the creation of medical devices that are designed to improve in flexibility toward a more natural state over the course of healing, while also controlling for the possibility of non-uniform in vivo erosion.

Abstract: A bimetal composite wire including, in cross-section, an outer shell or tube formed of a first biodegradable material and an inner core formed of a second biodegradable material. When formed into a stent, for example, the first and second biodegradable materials may be different, and may have differing biodegradation rates. In a first embodiment, the first biodegradable material of the shell may degrade relatively slowly for retention of the mechanical integrity of a stent during vessel remodeling, and the second biodegradable material of the core may degrade relatively quickly. In a second embodiment, the first biodegradable material of the shell may degrade relatively quickly, leaving a thinner structure of a second biodegradable material of the core that may degrade relatively slowly.

Abstract: Ti—Nb—Hf/Zr—(Cr) alloy shape-memory wires are provided which are suitable for use in medical devices and actuators, and methods for manufacturing such wires are provided. The present shape-memory Ti—Nb—Hf/Zr—(Cr) alloy is a superelastic wire material particularly suited for in vivo applications. For example, the present Ti—Nb—Hf/Zr—(Cr) alloy wire is radiopaque, thereby enabling surgical use of a monolithic, shape-memory alloy wire while preserving the ability to monitor the in vivo location of the wire through X-ray or other radiation-based imaging systems. In addition, the present Ti—Nb—Hf/Zr—(Cr) alloy can be manufactured to exhibit shape-memory alloy material properties without the use of nickel as an alloy constituent, thereby accommodating nickel-sensitive patients. The present Ti—Nb—Hf/Zr—(Cr) alloy can also be processed to exhibit a martensite/austenite transformation temperature near body-temperature, i.e., 37° C., so that shape-memory effects can be utilized to accomplish work in vivo.

Abstract: A spool for use in a wire braiding machine, for example, which has a “bi-tapered” design including a central cylindrical section and a pair of tapered (e.g., frusto-conical or parabolic) flanges having surfaces that slope inwardly toward the cylindrical section. In this manner, the spool provides a progressively widening wire fill area, as measured along a direction parallel to the rotational axis of the bobbin, as the wound wire advances progressively radially outwardly from the cylindrical section. This widening wire fill area aids in preventing the formation, propagation and buildup of wire winding defects, such that the wire is more likely to unspool or pay-out from the spool without losing tension, snagging or breaking.

Abstract: Fatigue damage resistant metal or metal alloy wires have a submicron-scale or nanograin microstructure that demonstrates improved fatigue damage resistance properties, and methods for manufacturing such wires. The present method may be used to form a wire having a nanograin microstructure characterized by a mean grain size that is 500 nm or less, in which the wire demonstrates improved fatigue damage resistance. Wire manufactured in accordance with the present process may show improvement in one or more other material properties, such as ultimate strength, unloading plateau strength, permanent set, ductility, and recoverable strain, for example. Wire manufactured in accordance with the present process is suitable for use in a medical device, or other high end application.

Abstract: A test apparatus and method for determining at least one characteristic of a test specimen. An exemplary test specimen is a shape memory metal alloy and an exemplary characteristic is a transformation temperature of the shape memory metal alloy. The test apparatus may include a chiller unit including a tank containing a chilling medium, such as isopropyl alcohol or denatured alcohol, which holds a removable fixture tray that can accommodate up to ten specimens, or more. The fixture tray holds the test specimens in an initial deformed condition, and the cooling medium may be gradually heated to induce transformation of the specimens. The test apparatus may include a vision-based optical system which includes a camera that tracks the specimens within its field of view.

Abstract: Wire products, such as round and flat wire, strands, cables, and tubing, are made from a shape memory material in which inherent defects within the material are isolated from the bulk material phase of the material within one or more stabilized material phases, such that the wire product demonstrates improved fatigue resistance. In one application, a method of mechanical conditioning in accordance with the present disclosure isolates inherent defects in nickel-titanium or NiTi materials in fields of a secondary material phase that are resistant to crack initiation and/or propagation, such as a martensite phase, while the remainder of the surrounding defect-free material remains in a primary or parent material phase, such as an austenite phase, whereby the overall superelastic nature of the material is preserved.

Abstract: A method for fusing a pair of insulated wires to one another, and a fused wire made by such method, in which the combined or major diameter of the fused wire equals, or very closely matches, the sum of the diameters of the individual wires prior to fusion. In the present method, a pair of wires, each having a coating of insulation that is substantially fully cured, are brought into close abutting contact with one another along a line contact, and thereafter pass through a heating device which heats the coatings above their a thermal transition point of at least one of the pair of wires to fuse the coatings of the wires together along the line contact.