A method for producing a timepiece spring includes the following steps: producing a piece based on silicon, having the desired shape of the timepiece spring; thermally oxidising the piece; deoxidising the piece; annealing the piece in a reducing atmosphere; forming a silicon oxide layer on the piece.

Disclosed is a method including: a) obtaining a substrate extending in a predetermined plane with a first layer parallel to the plane; b) forming a through-hole in the first layer; c) depositing a second layer on the first, the second layer filling the a through-hole to form a bridge of material; d) etching a hairspring in an etching layer made up of the second layer or the substrate, the one of the second layer and the substrate in which the a hairspring is not etched constituting a support, the bridge of material connecting the hairspring to the support perpendicular to the predetermined plane; e) removing the first layer, the hairspring remaining attached to the support by the bridge of material; f) subjecting the hairspring to a thermal treatment; and g) detaching the hairspring from the support.

A spiral spring intended to equip a balance of a horological movement, wherein the spiral spring is made of an alloy consisting of Nb, Ti and at least one element selected from Zr and Hf, optionally at least one element selected from W and Mo, possible traces of other elements selected from O, H, Ta, C, Fe, N, Ni, Si, Cu, Al, with the following weight percentages: a content of Nb comprised between 40 and 84%, a total content of Ti, Zr and Hf comprised between 16 and 55%, a content for W and Mo respectively comprised between 0 and 2.5%, a content for each of said elements selected from O, H, Ta, C, Fe, N, Ni, Si, Cu, Al comprised between 0 and 1600 ppm with the sum of said traces less than or equal to 0.3% by weight. The method for manufacturing the spiral spring is also disclosed.

A spiral spring is configured to equip a balance of a horological movement. The spiral spring is made of an alloy consisting of: Nb, Ti and at least one element selected from V and Ta, optionally at least one element selected from Zr and Hf, optionally at least one element selected from W and Mo, possible traces of other elements selected from O, H, C, Fe, N, Ni, Si, Cu, Al, with the following weight percentages: a total content of Nb, V and Ta comprised between 40 and 85%, a total content of Ti, Zr and Hf comprised between 15 and 55%, a content for W and Mo respectively comprised between 0 and 2.5%, a content for each of the elements selected from 0, H, C, Fe, N, Ni, Si, Cu, Al between 0 and 1600 ppm with the sum of the traces less than or equal to 0.3% by weight.

The invention relates to a method which comprises the steps of providing a plate (2) made of a micromachinable material, forming the timepiece component (1) with at least one attachment (3) for keeping the component attached to the rest of the plate (2), by etching the plate (2); and creating, along a desired breakage line of the attachment, a pre-detachment area (4) comprising at least one gap (5) obtained by etching into the body of the plate (2).

A timepiece includes a mechanical oscillator, formed by a balance and a piezoelectric balance spring, and a regulating device for regulating the frequency of the mechanical oscillator which is arranged to be able to produce time-separated regulating pulses, each consisting of a momentary decrease in an electrical resistance applied by the regulating device between two electrodes of the balance spring relative to a nominal electrical resistance. Each regulating pulse produces a variation of rate which varies as a function of its moment of starting in a half-period of the mechanical oscillator, the characteristic function of this variation of rate relative to the moment of starting of at least one regulating pulse respectively in at least one half-period of the mechanical oscillator being negative in a first temporal zone of at least one half-period and positive in a second temporal zone of at least one half-period.

A process for producing a metal alloy balance wheel by molding includes a) making a mold in the negative shape of the balance wheel; b) obtaining a metal alloy that has a thermal expansion coefficient of less than 25 ppm/° C. and is able to be in an at least partly amorphous state when it is heated to a temperature between its glass transition temperature and its crystallization temperature; c) putting the metal alloy into the mold, the metal alloy being heated to a temperature between its glass transition temperature and its crystallization temperature so as to be hot-molded and to form a balance wheel; d) cooling the metal alloy to obtain a balance wheel made of the metal alloy; and e) releasing the balance wheel obtained in step d) from its mold. The process also includes a step for over-molding flexible centering components in the hub.

A process for fabricating a hairspring having a final stiffness includes the steps of fabricating a hairspring to thickened dimensions, and determining the initial stiffness of the hairspring formed in order to remove the volume of material to obtain the hairspring having the dimensions required for said final stiffness.

A balance spring for a balance with a blank containing: niobium: the remainder to 100 wt %, titanium: between 40 and 60 wt %, traces of elements selected from the group formed of O, H, C, Fe, Ta, N, Ni, Si, Cu, Al, between 0 and 1600 ppm by weight individually, and less than 0.3 wt % combined, a step of β-quenching the blank with a given diameter, such that the titanium of the alloy is essentially in solid solution form with β-phase niobium, the α-phase titanium content being less than or equal to 5% by volume, at least one deformation step of the alloy alternated with at least one heat treatment step such that the niobium and titanium alloy obtained has an elastic limit higher than or equal to 600 MPa and a modulus of elasticity lower than or equal to 100 GPa, a winding step to form the balance spring being performed prior to the final heat treatment step, prior to the deformation step, a step of depositing, on the alloy blank, a surface layer of a ductile material such as copper, the surface layer of ductile material being retained on the balance spring, the thermoelastic coefficient of the niobium and titanium alloy being adapted accordingly.

The invention relates to a compacted and densified metal material having one or more phases formed of an agglomerate of grains, the cohesion of the material being provided by bridges formed between grains, said material having a relative density higher than or equal to 95% and preferably higher than or equal to 98%.