Abstract: Superelastic and/or shape memory nickel-titanium alloys having an increased fatigue life that is superior to known nickel-titanium alloys are disclosed. The nickel-titanium alloys have a minimum fatigue life that may be at least about 10 million strain cycles at a strain of at least about 0.75. The minimum fatigue life may be due, at least in part, to the nickel-titanium alloy having at least one of an oxygen concentration of less than about 200 ppm, a carbon concentration of less than about 200 ppm, the absence of oxide-based and/or carbide-based inclusions having a size greater than about 5 microns (?m), the presence of an R-phase, or combinations of the foregoing. Articles manufactured from such fatigue-resistant nickel-titanium alloys can be more durable because they are more resistant to repetitive strain and crack propagation.

Abstract: Shape-setting methods for fabricating devices made of single crystal shape memory alloys. The method include drawing a single crystal of a shape memory alloy from a melt of the alloy. This is followed by heating and quenching the crystal sufficiently rapid to limit the formation of alloy precipitates to an amount which retains hyperelastic composition and properties of the crystal.

Abstract: According to the invention, compositions of Ni—Ti—Pt high temperature, high force, shape memory alloys are disclosed that have transition temperatures above 100° C.; have narrow hysteresis; and produce a high specific work output.

Abstract: A damping and shock absorbing method and apparatus for permanent or non-permanent use in the human body and having a shape memory alloy material cycled through stress-strain hysteresis to dissipate energy for effective damping. A sufficiently high pre-stress is applied to the damping element(s) to ensure that the damping working range is within the superelastic cycle. The damping apparatus can work in tension or compression or both in tension and compression. Moreover, damping elements from a shape memory alloy can also work in flexion and extension as well in rotation. The damping apparatus can have a stroke and force suitable for use in the human body by the design, the structure and the chemical composition of the shape memory alloy and their pre-set properties, such as plateau stresses of the superelastic cycle depend on the ambient temperature, the force of damping elements can also be changed in-situ by changing the temperature of the damping elements.

Abstract: An active material assembly is provided having a thermally-activated active material apparatus with an elongated, non-planar shape and a thermoelectric device in thermal contact therewith. The thermoelectric device is characterized by a thermal differential when current flows through the device to activate the thermally-activated active material apparatus, thereby altering at least one dimension thereof. Multiple discrete thermoelectric devices may be in thermal contact with the active material apparatus and electrically in parallel with one another. The active material apparatus, which may be multiple active material components, each with one of the thermoelectric devices thereon, may be encased within a flexible electronic-insulating material to form an articulated active material assembly that can achieve different geometric shapes by separately activating one or more of the different thermoelectric devices. A method of fabricating an articulated active material assembly is also provided.

Abstract: A high fatigue life superelastic nickel-titanium (nitinol) wire, ribbon, sheet, tubing, or the like is disclosed. The nitinol has a 54.5 to 57.0 weight percent nickel with a balance of titanium composition and has less than 30 percent cold work as a final step after a full anneal and before shape setting heat treatment. Through a rotational beam fatigue test, fatigue life improvement of 37 percent has been observed.

Abstract: Methods of selectively treating linear elastic materials to produce localized areas of superelasticity and/or shape-memory are disclosed. In an illustrative method, a linear elastic workpiece may be formed into a particular shape by cold-forming or other low-temperature process, and incorporated into a medical device such as an embolic protection filter, vena cava filter, stent or guidewire. A heat source may be used to apply thermal energy to selective areas of the workpiece, imparting superelasticity to the material.

Abstract: A portable electronic device (100) includes a controllable skin texture surface that includes a skin texture surface actuation structure having a plurality of hinged elements (802-808) with a shape memory alloy (812) coupled thereto to effect movement of the hinged elements and a flexible skin structure (320) to change a tactile configuration of at least a portion of the controllable skin texture surface. A method also includes controlling a first shape memory alloy to actuate a plurality of hinged elements and in response, controlling a second shape memory alloy to actuate a hinged lock structure to lock a plurality of hinged elements in a first position. The method also includes deactivating the first shape memory alloy and unlocking the plurality of hinged elements by actuating the first shape memory alloy to allow the hinged lock to disengage. Corresponding structure is also disclosed.

Abstract: An active material hood impact mitigation mechanism is activated in response to a signal generated from an impact sensor or pre-impact sensor or manually. The mitigation mechanism is capable of changing either reversibly or irreversibly the stiffness, shape, location, orientation, or displacement force of the hood either globally or locally, before an impact against the hood. The active material mitigation mechanism is held in a device designed to be installed in operative communication with the hood surface. The active material is characterized by a first shape or stiffness and is operative to change to a second shape or stiffness in response to the activation signal. Such active materials include shape memory alloys, electroactive polymers, shape memory polymers, magnetic shape memory alloys, magnetorheological fluids, magnetorheological elastomers, electrorheological fluids, and piezoelectric materials.

Abstract: A composite element comprises:(a) a metal or metal alloy component having an elastic modulus that decreases with increasing temperature in a temperature range; and (b) sufficient amount of a shape memory alloy component having an elastic modulus that shows an increase in elastic modulus with increasing temperature in the said temperature range, such that the elastic modulus of the composite element does not fall substantially as the temperature is increased across the said temperature range. An article comprising such a composite element is suitable for use in high temperature applications, including motor vehicle components.

Abstract: A shape memory alloy comprises Co, Ni and Al with a two-phase structure comprising a ?-phase having a B2 structure and a ?-phase having an fcc structure, at least 40% by area of crystal grain boundaries of the ?-phase being occupied by the ?-phase. The shape memory alloy can be produced by a first heat treatment step comprising heating at 1200 to 1350° C. for 0.1 to 50 hours and cooling at 0.1 to 1000° C./minute, and a second heat treatment step comprising heating at 1000 to 1320° C. for 0.1 to 50 hours and cooling at 10 to 10000° C./minute.

Abstract: High-strength, low-hysteresis TiNi-based shape-memory alloys (SMAS) employing fully coherent low-misfit nanoscale precipitates, wherein the precipitate phase is based on an optimized composition for high parent-phase strength and martensite phase stability, and compensating the stored elastic energy through the addition of martensite stabilizers. The alloys, with a yield strength in excess of 1200 MPa, are useful for applications such as self-expanding stents, automotive actuators, and other applications wherein SMAs with high output force and long cyclic life are desired.

Abstract: An improved guiding member for use within a body lumen having a unique combination of superelastic characteristics. The superelastic alloy material has a composition consisting of about 30% to about 52% (atomic) titanium, and about 38% to 52% nickel and may have one or more elements selected from the group consisting of iron, cobalt, platinum, palladium, vanadium, copper, zirconium, hafnium and niobium. The alloy material is subjected to thermomechanical processing which includes a final cold working of about 10 to about 75% and then a heat treatment at a temperature between about 450° and about 600° C. and preferably about 475° to about 550° C. Before the heat treatment the cold worked alloy material is preferably subjected to mechanical straightening. The alloy material is preferably subjected to stresses equal to about 5 to about 50% of the room temperature ultimate yield stress of the material during the thermal treatment.

Abstract: A process comprising the steps of providing a precursor for an implantable medical device, at least a portion of the precursor made of a shape memory material, the shape memory material having a receptacle for receiving a marker therein, the shape memory material having an austenitic and a martensitic phase; enlarging the receptacle while the shape memory material is in the martensitic phase; inserting a marker in the receptacle while the shape memory material is in the martensitic phase; and thereafter transforming the precursor to the austenitic phase.

Abstract: An improved guiding member for use within a body lumen having a unique combination of superelastic characteristics. The superelastic alloy material has a composition consisting of about 30% to about 52% (atomic) titanium, and about 38% to 52% nickel and may have one or more elements selected from the group consisting of iron, cobalt, platinum, palladium, vanadium, copper, zirconium, hafnium and niobium. The alloy material is subjected to thermomechanical processing which includes a final cold working of about 10 to about 75% and then a heat treatment at a temperature between about 450° and about 600° C. and preferably about 475° to about 550° C. Before the heat treatment the cold worked alloy material is preferably subjected to mechanical straightening. The alloy material is preferably subjected to stresses equal to about 5 to about 50% of the room temperature ultimate yield stress of the material during the thermal treatment.

Abstract: A reconfigurable tool and/or die geometry and methods of use generally comprise forming at least a portion of a shape defining surface with a shape memory material. In response to an activation signal, the shape memory material changes geometry of the shape defining surface to provide a means for forming parts with different geometries from the same tool and/or die. In an alternative embodiment, an insert for a tool and/or die can be used, wherein the insert has at least a portion of its shape defining surface formed of a shape memory material. Also disclosed are processes for forming a first part with a defined geometry and a second part with a defined geometry different from the first part defined geometry using a reconfigurable tool and/or die as well as a reconfigurable insert with a standard tool and/or die.

Abstract: A memory metal expands through the use of a catalyst and a fuel-oxidizer mixture. The catalyst can be placed directly onto the surface of the memory metal, or it can just be in the proximity of the metal. The fuel-oxidizer mixture similarly can be placed on the surface of the metal or just near the metal. The oxidation of the fuel can be initiated by a spark, heat, or some other source, and the heat from the exothermic reaction raises the temperature of and causes the expansion of the memory metal.

Abstract: A cardiac harness for treating congestive heart failure is disclosed. The harness applies elastic, compressive reinforcement on the left ventricle to reduce deleterious wall tension and to resist shape change of the ventricle during the mechanical cardiac cycle. Rather than imposing a dimension beyond which the heart cannot expand, the harness provides no hard limit over the range of diastolic expansion of the ventricle. Instead, the harness follows the contour of the heart throughout diastole and continuously exerts gentle resistance to stretch. Also disclosed is a method of delivering the cardiac harness to the heart minimally invasively.

Abstract: A method of mounting a tire on a rim includes selecting a tire comprising bead cores, stretching the bead cores, sliding the bead cores over a balcony portion of the rim, allowing the bead cores to elastically return to lengths corresponding to diameters of respective seats of the rim, and inflating the tire. The bead cores include one or more portions of material with characteristics of superelasticity and shape memory. Stretching the bead cores may include applying constant load to the bead cores at ambient temperature and/or causing the bead cores to undergo structural change at ambient temperature. The structural change may include complete or partial change from austenitic structure to martensitic structure. The one or more portions of material are deformable at ambient temperature in response to a constant force and recover to original shape upon removal of the constant force.

Abstract: The present invention provides for Cu—Zn—Al(6%) alloy and an improved process to lower the martensitic transformation temperature, by a low temperature re-betatising treatment from 110° C. to 30° C. i.e. a lowering of 80° C. wherein previously high temperature betatised material has been subjected to re-betatising at lower temperature in order to utilize the material suitably.

Abstract: A method of treating a shape memory alloy to improve its various characteristics and to cause it to exhibit a two-way shape memory effect. A raw shape memory alloy having a substantially uniformly fine-grained crystal structure is prepared and then its crystal orientations are arranged substantially in a direction suitable for an expected operational direction, such as tensile or twisting direction or the like, in which the shape memory alloy is expected to move when used in an actuator after the completion of the treatment.

Abstract: A method of attaching a first member of one of quartz and a ceramic to a metal member. The method includes creating a hole in the metal member, the hole being smaller in size than the size of the first member over a temperature range, heating the metal member to a temperature sufficient to expand the hole to allow insertion of the first member in the hole, inserting a portion of the first member into the hole, and cooling the metal member to form a joined structure of the first member and the metal member.

Abstract: A conductive hinge is made of a superelastic shape memory alloy such as nitinol (NiTi) having a large elastic strain limit for enabling the hinge to bend to a small radius during stowage and flexible return to a trained rigid hinge position by training the shape memory alloy to assume a predetermined deployed configuration when released from a stowage configuration. The hinge is trained by forging at a temperature above a training temperature. The hinge is stowed and released in the superelastic state to deploy solar cell panels as the hinges unfold to the trained deployed configuration.

Abstract: A material and method for adhering at least two materials that includes the step of interposing at least one intermediate layer between the two materials and associated adhesion material. The materials to be adhered exhibit at least one characteristic dissimilarity and the intermediate material interposed contains at least one shape memory alloy, the shape memory alloy capable of exhibiting -superelasticity.

Abstract: A method of generating force between a structure and an additional member, particularly for reinforcing an existing structure so that an additional member can share existing load. Pre-cooled or pre-heated shims of shape memory alloy (SMA) are inserted between the additional member and the existing structure, or between different sub-units of the additional member, or between the additional member and shoes fixed for this purpose to the existing structure. On subsequent warming or cooling the SMA shims expand to apply compressive forces to the portions of the structure, additional member or shoe(s) with which they are in contact on their opposite sides. Further compressive, tensile, flexural or torsional forces will be developed within other parts of the structure and additional member as a result of the shim expansion depending on the particular arrangement.

Abstract: Nickel-titanium alloys that have been deep drawn in a cold working process have linear pseudoelastic behavior without a phase transformation or onset of stress-induced martensite. A medical device made from a structural element which has been deep drawn and subsequently formed into a desired medical device geometry will experience such linear pseudoelastic behavior.

Abstract: Iron-manganese-silicon-based shape memory alloys comprising:

Abstract: Articles made of shape memory alloys having improved fatigue performance and to methods of treating articles formed from shape memory alloy materials by pre-straining the articles (or desired portions of the articles) in a controlled manner so that the resultant articles exhibit improved fatigue performance. The shape memory articles are preferably medical devices, more preferably implantable medical devices. They are most preferably devices of nitinol shape memory alloy, most particularly that is superelastic at normal body temperature. The pre-straining method of the present invention as performed on such articles includes the controlled introduction of non-recoverable tensile strains greater than about 0.20% at the surface of a desired portion of a shape memory alloy article. Controlled pre-straining operations are performed on the shape-set nitinol metal to achieve nonrecoverable tensile strain greater than about 0.20% at or near the surface of selected regions in the nitinol metal article.

Abstract: High-strength, low-hysteresis TiNi-based shape-memory alloys (SMAS) employing fully coherent low-misfit nanoscale precipitates, wherein the precipitate phase is based on an optimized composition for high parent-phase strength and martensite phase stability, and compensating the stored elastic energy through the addition of martensite stabilizers. The alloys, with a yield strength in excess of 1200 MPa, are useful for applications such as self-expanding stents, automotive actuators, and other applications wherein SMAs with high output force and long cyclic life are desired.

Abstract: The present invention employs a shape memory alloy that exhibits a two-way shape memory effect and that has a stress-strain property that, in a stress-strain diagram, the stress-strain curve comprises a gentler gradient portion extending with relatively small gradients and a steeper gradient portion extending with relatively great gradients. The shape memory alloy is operated in the region surrounded by the gentler gradient portion, the steeper gradient portion, a practical stress limit line, a straight line connecting the intersection of the practical stress limit line and a strain limit line near shape recovery completion on which the strain of the shape memory alloy reaches a specified value in a state close to the shape recovery completion and the point where the strain is zero at a low temperature in the stress-strain diagram.

Abstract: An improved guiding member for use within a body lumen having a unique combination of superelastic characteristics. The superelastic alloy material has a composition consisting of about 30% to about 52% (atomic) titanium, and about 38% to 52% nickel and may have one or more elements selected from the group consisting of iron, cobalt, platinum, palladium, vanadium, copper, zirconium, hafnium and niobium. The alloy material is subjected to thermomechanical processing which includes a final cold working of about 10 to about 75% and then a heat treatment at a temperature between about 4500° and about 600° C. and preferably about 4750° to about 5500° C. Before the heat treatment the cold worked alloy material is preferably subjected to mechanical straightening. The alloy material is preferably subjected to stresses equal to about 5 to about 50% of the room temperature ultimate yield stress of the material during the thermal treatment.

Abstract: A composition of a porous body for use as biomaterial according to the present invention is produced by adding Al (aluminum) in the amount of 0.1 to 3.0 atomic % to a porous composition consisting of titanium, nickel, iron and molybdenum, and it promotes the growth of living tissue and cells into pores. By the addition of Al to Ni, Ti, Fe and Mo, the temperature of formation of the liquid phase is lowered, and thus the diffusion of the constitutional elements of the composition is promoted, and the uniform distribution of the constitutional elements increases. As a result, the proportion of micropores in the porous body becomes increased to the extent that the distribution of micropores having the size in the range of 10−2 &mgr;m˜10 &mgr;m is more than 5% in the metal bridge.

Abstract: A piece of jewelry (10) is disclosed, comprising first and second substantially opposing end portions (14, 16), at least one said end potion being moveable from an open state A in which said end portions (14, 16) are spaced apart towards a closed state B in which said end portions (14, 16) are spaced apart by, a reduced gap or are substantially engaged. The piece of jewelry (10) comprises at least a section (12a) made from a shape memory material and said shape memory material is adapted, at or above a predetermined temperature Ta, to bring said end portions (14, 16) towards each other. This occurs preferably when said shape memory material is placed in the region of a body part of a wearer such that shape memory effect is used in co-operation with body temperature to fit said piece of jewelry to its wearer whist simultaneously causing, a change in externally visible shape or configuration or the jewelry.

Abstract: Impact resistant components and methods of protecting structures from impacts. The components are interposed between a potential point of impact and a structure to be protected. They comprise a shape memory alloy (SMA) exhibiting pseudoelastic behavior, and having a high strain to failure.

Abstract: The present invention discloses devices and a method of fabrication of devices using a shape memory effect, thin film with a compositional gradient through the thickness of the film. Specifically, a NiTi SME thin film is disclosed that can be used in actuators, MEMS devices and flow control. The process of fabrication includes a gradual heating of the target over time during the sputter deposition of a thin film on a substrate under high vacuum, without compositional modification. The resulting thin film exhibits two-way shape memory effect that can be cyclically applied without an external bias force.

Abstract: This invention relates to a process for manufacturing, shaping, and machining of a part made of a shape memory alloy, comprising a single step in which the said part is fabricated, shaped and machined simultaneously in a single operation by a cutting machining process such as turning. The invention is also related to the part prepared by this process, which is particularly a helical spring with adjacent turns. In particular, this part may be used in actuator or actuator/sensor type devices.

Abstract: An improved guiding member for use within a body lumen having a unique combination of superelastic characteristics. The superelastic alloy material has a composition consisting of about 30% to about 52% (atomic) titanium, and about 38% to 52% nickel and may have one or more elements selected from the group consisting of iron, cobalt, platinum, palladium, vanadium, copper, zirconium, hafnium and niobium. The alloy material is subjected to thermomechanical processing which includes a final cold working of about 10 to about 75% and then a heat treatment at a temperature between about 450° and about 600° C. and preferably about 475° to about 550° C. Before the heat treatment the cold worked alloy material is preferably subjected to mechanical straightening. The alloy material is preferably subjected to stresses equal to about 5 to about 50% of the room temperature ultimate yield stress of the material during the thermal treatment.

Abstract: A NbC-added Fe—Mn—Si-based shape memory alloy is provided, showing a shape memory property even if a special treatment such as training is not performed.

Abstract: A bead core for locking a tire to a seat of a wheel rim includes a plurality of annular reinforcement elements having an inner transverse dimension smaller than a maximum diameter of the wheel rim, and being sufficiently deformable at ambient temperature to facilitate mounting the tire onto the wheel rim. The plurality of annular reinforcement elements includes at least one tightening element made of a shape-memory alloy responsive to temperature increases by increasing a tightening force on the wheel rim at a predetermined temperature. A tire including the bead core and a method for securing a tire to a rim using the bead core are also disclosed.

Abstract: A method of fabricating ternary TiNi-based alloys to achieve substantially higher phase-change transition temperatures in the resulting SMA materials and which have optimal thermo-mechanical properties. One target is provided which comprises the element Ti, a second target comprises the element Ni and a third target comprises an element which when combined with Ti and Ni can produce a shape memory alloy. The three targets are co-sputtered onto a substrate at rates which are controlled so that the sum of the percentage composition of the elements that are from the left side of the periodic table are substantially 50 atomic percent, and the sum of percentage composition of the elements that are from the right side of the periodic table comprise the remaining 50 atomic percent.

Abstract: An improved guiding member for use within a body lumen having a unique combination of superelastic characteristics. The superelastic alloy material has a composition consisting of about 30% to about 52% (atomic) titanium, and about 38% to 52% nickel and may have one or more elements selected from the group consisting of iron, cobalt, platinum, palladium, vanadium, copper, zirconium, hafnium and niobium. The alloy material is subjected to thermomechanical processing which includes a final cold working of about 10 to about 75% and then a: heat treatment at a temperature between about 450° and about 600° C. and preferably about 475° to about 550° C. Before the heat treatment the cold worked alloy material is preferably subjected to mechanical straightening. The alloy material is preferably subjected to stresses equal to about 5 to about 50% of the room temperature ultimate yield stress of the material during the thermal treatment.

Abstract: A Ti—Ni shape memory alloy with ductility, including Ti of 50˜66 atomic % in a composition, and in which precipitation of Ti2Ni phases at grain boundaries is suppressed.

Abstract: A super-elastic titanium alloy for medical use consisting essentially of:

Abstract: A medical device for use within a body lumen that is made from a binary nickel-titanium alloy that remains in its austenitic phase throughout its operational range is disclosed. The medical device, such as an intraluminal stent, is made from superelastic nickel-titanium and may optionally be alloyed with a ternary element. By adding the ternary element and/or through heat treatment, it is possible to lower the phase transformation temperature between the austenitic phase and the martensitic phase of the nickel-titanium alloy. By lowering the phase transformation temperature, the martensite deformation temperature is likewise depressed. It is possible then to depress the martensite deformation temperature below body temperature such that when the device is used in a body lumen for medical treatment, the nickel-titanium device remains completely in the austenitic phase without appearance of stress-induced martensite even if the device is placed under stress.

Abstract: A shape metal alloy tendon and method for forming shape metal alloy tendons is presented. The shape metal alloy tendon has a shape metal alloy wire with an axis and a first and second end. A first metal sleeve is swagedly affixed to the first end. A second metal sleeve is swagedly affixed to second end.

Abstract: A bead wire for a bead core of a tire, having at least one portion of its annular extent formed from a material having characteristics of superelasticity, resulting in increasing deformations of the bead core when a constant stretching load is applied at constant temperature. As the load ceases, the bead core recovers from the deformation. The characteristics of the bead core allow mounting a tire incorporating the bead core to a rim at ambient temperature, with intelligent adjustment of the bead core to the dimensions of the seat of the rim. The bead core increases the magnitude of an inward contraction stress as its temperature increases, so that it increases the gripping pressure exerted by the tire beads on the rim when the tire runs in the deflated state.

Abstract: A method of fabricating ternary TiNi-based alloys to achieve substantially higher phase-change transition temperatures in the resulting SMA materials and which have optimal thermo-mechanical properties. One target is provided which comprises the element Ti, a second target comprises the element Ni and a third target comprises an element which when combined with Ti and Ni can produce a shape memory alloy. The three targets are co-sputtered onto a substrate at rates which are controlled so that the sum of the percentage composition of the elements that are from the left side of the periodic table are substantially 50 atomic percent, and the sum of percentage composition of the elements that are from the right side of the periodic table comprise the remaining 50 atomic percent.

Abstract: An improved guiding member for use within a body lumen having a unique combination of superelastic characteristics. The superelastic alloy material has a composition consisting of about 30% to about 52% (atomic) titanium, and about 38% to 52% nickel and may have one or more elements selected from the group consisting of iron, cobalt, platinum, palladium, vanadium, copper, zirconium, hafnium and niobium. The alloy material is subjected to thermomechanical processing which includes a final cold working of about 10 to about 75% and then a heat treatment at a temperature between about 450° and about 600° C. and preferably about 475° to about 550° C. Before the heat treatment the cold worked alloy material is preferably subjected to mechanical straightening. The alloy material is preferably subjected to stresses equal to about 5 to about 50% of the room temperature ultimate yield stress of the material during the thermal treatment.

Abstract: A diaphragm includes a vibratory membrane and at least one nickel titanium memory metal member having a shape that can be mechanically adjusted with a heating signal. The mechanical adjustment of the at least one nickel titanium memory metal member tunes the frequency response of the vibratory membrane in the diaphragm. The at least one nickel titanium memory metal member can be a sheet providing a vibratory membrane, or sheet sections or wire made of nickel titanium memory metal bonded to a vibratory membrane.

Abstract: The present invention provides for Cu—Zn—Al(6%) alloy and an improved process to lower the martensitic transformation temperature, by a low temperature re-betatising treatment from 110° C. to 30° C. i.e. a lowering of 80° C. wherein previously high temperature betatised material has been subjected to re-betatising at lower temperature in order to utilize the material suitably.