Methods for controlling properties of structural elements of implantable medical devices, where the structural elements contain shape memory alloys (SMAs) include promoting or inhibiting in vivo formation of R-phase crystal structure or converging or separating the R-phase from the austenite phase.

Provided is a method of making a polycrystalline shape memory alloy (SMA) by forming an alloy with grains and boundaries between them, exposing the alloy to a two-phase temperature range at which a two-phase equilibrium is achieved in the alloy, converting grains to an austenite phase, and precipitating a face-centered-cubic crystal structure solid solution phase at grain boundaries, then quenching the alloy. Also provided is a polycrystalline SMA with a dual-phase microstructure having grains mostly in an austenite phase, a martensite phase, or in transition between an austenite phase and a martensite phase and grain boundaries containing a face-centered-cubic crystal structure solid solution phase.

The invention relates to a method for producing a precipitation-strengthened shape memory alloy (SMA), comprising providing a composition designed according to property objectives of the precipitation-strengthened SMA, wherein the property objectives are design specifications of the precipitation-strengthened SMA; performing homogenization and solution treatment of the composition at a first temperature for a first period of time followed by water quenching to form an ingot; and aging treatment of the ingot at a second temperature for a second period of time followed by water quenching to form the precipitation-strengthened SMA.

The present invention provides a shape-memory alloy including a AuCuAl alloy having 20 at % or more and 40 at % or less Cu and 15 at % or more and 30 at % or less Al, with the balance being Au and inevitable impurities. The shape-memory alloy has a Vickers hardness of 360 Hv or less. The AuCuAl alloy of the present invention is an alloy capable of developing both biocompatibility and a shape-memory effect, and further capable of achieving artifactlessness in a magnetic environment. The AuCuAl alloy can be produced by heat-treating a clad material formed of a combination of a hollow material made of a AuCu alloy and a core material made of metallic Al at 500? C. or more and 700? C. or less.

Ternary and quaternary shape memory alloys, particularly nickel-titanium based quaternary and quaternary shape memory alloys, are disclosed and made by a method employing physical vapor deposition (PVD), such as by sputtering, of NiTiX, wherein X is a ternary metal constituent. By employing PVD processing, ternary and quaternary NiTi alloy bulk materials may be made in in the as-deposited state such that the configuration and conformation of a desired precursor material, e.g., wires, tubes, planar materials, curvilinear, or as the near finished end product, such as a hypotube for stent manufacture, semilunar for cardiac valves or conical for embolic or caval filters, is formed on a removable deposition substrate in the configuration and conformation of the precursor material or near-finished end product.

A nickel-titanium alloy with an average grain size of between 0.2 and 10 microns and a recoverable strain of greater than 9% is disclosed herein, in which the alloy is formed using a method which involves applying a shape set heat treatment to the nickel-titanium alloy. The heat treatment includes applying heat at a temperature between 225? C. and 350? C. for a period of time between 20 and 240 minutes.

A transformable garment that folds and envelops the wearer with a garment body with panels that use origami folding and shape memory alloy (SMA) elements to assist to transform the garment from an expanded state to a retracted state is provided. Garment designs with transformable panels and sleeves can benefit those who have trouble dressing by allowing the garment to wrap around and fit the wearer without outside help. These types of clothes are expected to be beneficial for people with Cerebral Palsy (CP) and also for populations with other body movement disorders and elderly people.

A method of forming a surface structure of a component of a medical devices includes forming a fatigue-resistant portion, which entails forming a first layer comprising a transition metal selected from the group consisting of Ta, Nb, Mo, V, Mn, Fe, Cr, Co, Ni, Cu, and Si on at least a portion of a surface of the component, where the surface comprises a nickel-titanium alloy, and alloying the transition metal of the first layer with the nickel-titanium alloy of the surface. The method further includes forming a rough outer surface of the fatigue-resistant portion, where the rough outer surface is adapted for adhesion of a material thereto.

An earth-boring tool includes a tool body having an aperture therein defining a nozzle port, a nozzle or nozzle assembly disposed in the nozzle port, and a shape memory material disposed adjacent a surface of at least one component of the nozzle or nozzle assembly. The shape memory material retains at least one component of the nozzle or nozzle assembly by a threadless connection. The threadless connection includes mechanical interference between the shape memory material, the at least one component of the nozzle or nozzle assembly, and the tool body or another component of the nozzle or nozzle assembly. The shape memory material is formulated and configured to transform from a first phase and a first shape upon heating and to transform from a second phase and a second shape upon cooling.

A method for treating a material comprising: applying energy to a predetermined portion of the material in a controlled manner such that the local chemistry of the predetermined portion is altered to provide a predetermined result. When the material is a shape memory material, the predetermined result may be to provide an additional memory to the predetermined portion or to alter the pseudo-elastic properties of the shape memory material. In other examples, which are not necessarily restricted to shape memory materials, the process may be used to adjust the concentration of components at the surface to allow the formation of an oxide layer at the surface of the material to provide corrosion resistance; to remove contaminants from the material; to adjust surface texture; or to generate at least one additional phase particle in the material to provide a nucleation site for grain growth, which in turn, can strengthen the material.