A method for vacuum heat treating Nb, such as is used in superconducting radio frequency cavities, to engineer the interstitial oxygen profile with depth into the surface to conveniently optimize the low-temperature rf surface resistance of the material. An example application is heating of 1.3 GHz accelerating structures between 250-400° C. to achieve a very high quality factor of 5×10.sup.10 at 2.0 K. With data supplied by secondary ion mass spectrometry measurements, application of oxide decomposition and oxygen diffusion theory was applied to quantify previously unknown parameters crucial in achieving the oxygen alloy concentration profiles required to optimize the rf surface resistance. RF measurements of vacuum heat treated Nb superconducting radio frequency cavities confirmed the minimized surface resistance (higher Q.sub.0) previously expected only from 800° C. diffusive alloying with nitrogen.

Metal components subject to wear or contact fatigue in a first area, and subject to bending, axial and/or torsional stress loading in a second area comprise a surface hardened, first surface layer in the first area, and a surface compressive-stress treated, second surface layer in the second area. The second surface layer has a material hardness different from, and typically lower than, the first surface layer, and induced residual compressive stress to improve fatigue strength. Example components described include a gear, a cog, a pinion, a rack, a splined shaft, a splined coupling, a torqueing tool and a nut driving tool. A hybrid manufacturing process is described, including area-selective surface hardening combined with a process to add compressive stress to fatigue failure prone areas.

The invention provides a method and a product for manufacturing a titanium alloy dual-structure turbine disk based on partial hydrogenation, which includes the following steps: coating a glass coating on the partial surface of a titanium alloy billet where hydrogen-blocking is required, and sintering the titanium alloy billet coated with the glass coating; performing hydrogenation treatment on the titanium alloy billet, such that the hydrogen concentration at the hydrogenation-required portion reaches the predetermined level; removing the glass coating from the titanium alloy billet; preheating the titanium alloy billet, and then performing high temperature die forging in the forging dies; performing vacuum dehydrogenation treatment on the forged turbine disk to remove hydrogen element inside the forging, so that the hydrogen content is 0.015 wt. % or less.

A method of case hardening a titanium part, including placing the titanium part within a chamber; evacuating or purging the chamber; heating the titanium part placed within the chamber; introducing a gas containing cyanogen into the chamber; and exposing the titanium part placed within the chamber to the introduced gas containing cyanogen.

A balance spring intended to equip a balance of a horological movement, wherein the balance spring is made of an alloy consisting of Nb, Ti, H and possible traces of other elements selected from O, C, Fe, N, Ni, Si, Cu and Al, with the following weight percentages: a Ti content comprised between 1 and 80 wt %, a H content comprised between 0.17 and 2 wt %, a total content of all other elements of less than or equal to 0.3 wt %, the remainder to 100 wt % consisting of Nb. A manufacturing method for the balance spring is also disclosed and includes a step of thermochemically treating a blank made of a Nb and Ti alloy in an atmosphere including hydrogen so as to enrich the Nb and Ti alloy with hydrogen in interstitial form.

Systems and methods disclosed herein relate to the manufacture of metallic material with a thermal expansion coefficient in a predetermined range, comprising: deforming, a metallic material comprising a first phase and a first thermal expansion coefficient. In response to the deformation, at least some of the first phase is transformed into a second phase, wherein the second phase comprises martensite, and orienting the metallic material in at least one predetermined orientation, wherein the metallic material, subsequent to deformation, comprises a second thermal expansion coefficient, wherein the second thermal expansion coefficient is within a predetermined range, and wherein the thermal expansion is in at least one predetermined direction. In some embodiments, the metallic material comprises the second phase and is thermo-mechanically deformed to orient the grains in at least one direction.

Systems and methods disclosed herein relate to the manufacture of metallic material with a thermal expansion coefficient in a predetermined range, comprising: deforming, a metallic material comprising a first phase and a first thermal expansion coefficient. In response to the deformation, at least some of the first phase is transformed into a second phase, wherein the second phase comprises martensite, and orienting the metallic material in at least one predetermined orientation, wherein the metallic material, subsequent to deformation, comprises a second thermal expansion coefficient, wherein the second thermal expansion coefficient is within a predetermined range, and wherein the thermal expansion is in at least one predetermined direction. In some embodiments, the metallic material comprises the second phase and is thermo-mechanically deformed to orient the grains in at least one direction.

The present invention relates to a spiral spring for a balance wheel made of an alloy of niobium and titanium with an essentially single-phase structure, and the method of manufacture thereof which comprises: a step of producing a blank in a niobium-based alloy consisting of: niobium: balance to 100 wt %, titanium: between 40 and 49 wt %, traces of elements selected from the group consisting of O, H, C, Fe, Ta, N, Ni, Si, Cu, Al, between 0 and 1600 ppm by weight individually, and cumulatively less than 0.3 wt %, a step of type β hardening of said blank at a given diameter, in such a way that the titanium of the niobium-based alloy is essentially in the form of a solid solution with niobium in β phase, the content of titanium in α phase being less than or equal to 10 vol %, at least one deformation step of said alloy alternating with at least one step of heat treatment, the number of steps of heat treatment and of deformation being limited so that the niobium-based alloy obtained retains a structure in which the titanium of the niobium-based alloy is essentially in the form of a solid solution with niobium in β phase, the content of titanium in α phase being less than or equal to 10 vol % and it has an elastic limit greater than or equal to 600 MPa and an elastic modulus less than or equal to 100 GPa, a step of winding to form the spiral spring being carried out before the last heat treatment step.

The present invention relates to a spiral spring for a balance wheel made of an alloy of niobium and titanium with an essentially single-phase structure, and the method of manufacture thereof which comprises: a step of producing a blank in a niobium-based alloy consisting of: niobium: balance to 100 wt %, titanium: between 40 and 49 wt %, traces of elements selected from the group consisting of O, H, C, Fe, Ta, N, Ni, Si, Cu, Al, between 0 and 1600 ppm by weight individually, and cumulatively less than 0.3 wt %, a step of type β hardening of said blank at a given diameter, in such a way that the titanium of the niobium-based alloy is essentially in the form of a solid solution with niobium in β phase, the content of titanium in α phase being less than or equal to 10 vol %, at least one deformation step of said alloy alternating with at least one step of heat treatment, the number of steps of heat treatment and of deformation being limited so that the niobium-based alloy obtained retains a structure in which the titanium of the niobium-based alloy is essentially in the form of a solid solution with niobium in β phase, the content of titanium in α phase being less than or equal to 10 vol % and it has an elastic limit greater than or equal to 600 MPa and an elastic modulus less than or equal to 100 GPa, a step of winding to form the spiral spring being carried out before the last heat treatment step.

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.