Turbomachine stator sector having flexible regions subjected to high stress

A turbine stator sector comprising a plurality of vanes extending along a radial direction between a first end and a second end and along an axial direction between a leading edge and a trailing edge, said sector further comprising an internal shroud linked to the first end of the plurality of vanes and an external shroud linked to the second end of the plurality of vanes,

• wherein the turbine stator sector comprises at least one annular portion forming all or part of the internal shroud or of the external shroud, said at least one annular portion comprising a first partition at a junction with the first or second end of the plurality of vanes and a second partition held spaced from the first partition along the radial direction by a three dimensional structure, wherein the internal shroud includes a fore end and an aft end, wherein the three dimensional structure of the external shroud extends past the aft end of the internal shroud, wherein the at least one annular portion of the external shroud extends past a terminal end of one or more protruding tabs along the axial direction, wherein the three dimensional structure includes a plurality of cutouts, and wherein vanes of the plurality of vanes are integral with the internal shroud and with the external shroud, and the at least one annular portion being in a single piece with the internal shroud or the external shroud.