SPACER GRID FOR POSITIONING OF FUEL RODS Russian patent published in 2012 - IPC C22F1/18 G21C3/34 

FIELD: metallurgy.

SUBSTANCE: method for obtaining metal sheet (1) from zirconium-based alloy with Kerns factor close to 0.33 in the direction perpendicular to rolling direction, for manufacture of spacer grid. Metal sheet (1) has longitudinal axis A, transverse axis B, which determine the sheet plane (BA). Method involves a stage for obtaining sheet (2) from zirconium-based alloy; at that, sheet (2) is subject at least to one preparatory cold rolling and final cold rolling, which are carried out in one direction along longitudinal axis (A). Heat treatment of sheet (2) is performed between preparatory and final rolling so that partial recrystallisation of zirconium-based alloy with degree of not more than 90% is performed. Method for obtaining spacer grid (3) which restricts grid (5) cells for fuel rods. Cutting of sheet (1) into strips (4) is performed so that their longitudinal axes (B) are perpendicular to rolling direction. Strips (4) are arranged so that spacer grid (3) can be formed and so that longitudinal axes (B) of metal strips (4) are perpendicular to longitudinal direction (6) of grid cells (5).

EFFECT: slow growth at least in one direction is found out in metal sheet.

27 cl, 2 dwg