An assembly (300) includes (i) a hairspring (2) made of a paramagnetic alloy including at least one of the following elements: Nb, V, Ta, Ti, Zr and Hf, notably an alloy including the elements Nb and Zr with between 5% and 25% by mass of Zr and an interstitial doping agent including oxygen, and (ii) at least one fastening part (1; 1), notably two parts (1; 1), in particular a stud (1) or a collet (1), for an end (2a; 2b) of the hairspring (2), the at least one part (1; 1) having a first portion (10; 10) that is designed to come into contact with the hairspring (2) and that is made of titanium or titanium alloy or of tantalum or tantalum alloy, notably grade 2 titanium or grade 5 titanium.

An assembly (300) includes (i) a hairspring (2) made of a paramagnetic alloy including at least one of the following elements: Nb, V, Ta, Ti, Zr and Hf, notably an alloy including the elements Nb and Zr with between 5% and 25% by mass of Zr and an interstitial doping agent including oxygen, and (ii) at least one fastening part (1; 1), notably two parts (1; 1), in particular a stud (1) or a collet (1), for an end (2a; 2b) of the hairspring (2), the at least one part (1; 1) having a first portion (10; 10) that is designed to come into contact with the hairspring (2) and that is made of titanium or titanium alloy or of tantalum or tantalum alloy, notably grade 2 titanium or grade 5 titanium.

The invention relates to a method for fabrication of a part intended to be welded comprising a final machining step capable of reducing the contact surface of the face to be welded.

The invention relates to a method for fabrication of a part intended to be welded comprising a final machining step capable of reducing the contact surface of the face to be welded.

An assembly (1) for attaching a free end (8) of an outer last coil (10) of a balance spring (12) for a horological movement, this attachment assembly (1) including a stud (2) and a blocking element (14), the stud (2) being provided with a groove (6) in which the free end (8) of the outer last coil (10) of the balance spring (12) is engaged, the blocking element (14) also being engaged in the groove (6), in contact with the outer last coil (10) of the balance spring (12), the attachment assembly (1) further including a clamping member (16) which presses the blocking element (14) against the free end (8) of the outer last coil (10) of the balance spring (12), such that the free end (8) of the outer last coil (10) of the balance spring (12) is immobilised in the groove (6) of the stud (2).

An assembly (1) for attaching a free end (8) of an outer last coil (10) of a balance spring (12) for a horological movement, this attachment assembly (1) including a stud (2) and a blocking element (14), the stud (2) being provided with a groove (6) in which the free end (8) of the outer last coil (10) of the balance spring (12) is engaged, the blocking element (14) also being engaged in the groove (6), in contact with the outer last coil (10) of the balance spring (12), the attachment assembly (1) further including a clamping member (16) which presses the blocking element (14) against the free end (8) of the outer last coil (10) of the balance spring (12), such that the free end (8) of the outer last coil (10) of the balance spring (12) is immobilised in the groove (6) of the stud (2).

The method of manufacturing a timepiece shaft (1) includes grinding a ceramic piece, especially to form a balance shaft (1), having a functional portion (2a; 2b) including at least one part (221a; 221b) of a pivot-shank (22a; 22b) and/or at least one part (211a; 211b) of a pivot (21a; 21b), the first functional portion being made of ceramic and a first outer diameter (D1) of the first functional portion being less than 0.5 mm, or less than 0.4 mm, or less than 0.2 mm, or less than 0.1 mm.

The method of manufacturing a timepiece shaft (1) includes grinding a ceramic piece, especially to form a balance shaft (1), having a functional portion (2a; 2b) including at least one part (221a; 221b) of a pivot-shank (22a; 22b) and/or at least one part (211a; 211b) of a pivot (21a; 21b), the first functional portion being made of ceramic and a first outer diameter (D1) of the first functional portion being less than 0.5 mm, or less than 0.4 mm, or less than 0.2 mm, or less than 0.1 mm.

A method for fabrication of a part intended to be welded including a step for forming an oblique wall between two perpendicular surfaces capable of reducing the contact surface of the face to be welded.

A method for fabrication of a part intended to be welded including a step for forming an oblique wall between two perpendicular surfaces capable of reducing the contact surface of the face to be welded.