Structural part for a nuclear reactor fuel assembly and method for producing this structural part

A method for producing a structural part, which comprises:

• a) annealing a starting body of a zirconium alloy at a temperature in the .beta. range below the melting temperature to dissolve precipitated-out alloy ingredients, then quenching the starting body at a quenching rate of at least 30 K/s at a surface of the starting body, at a temperature transition through the .alpha.+.beta. range in which both hexagonal and body-centered cubic crystal structures are present in the zirconium alloy;
• b) hot-forging the starting body into a forged part at a first temperature in the .alpha. range;
• c) then heating the forged part to a second temperature in the .alpha. range above the first temperature, until formation of sediments of the alloy ingredients having a precipitate diameter with a the geometric mean value in a range of substantially from 0.1 to 0.3 .mu.m;
• d) then hot-rolling or hot-extruding the forged part at a temperature in the .alpha. range below the second temperature;
• and
• e) then cold-rolling the hot-rolled forged part in at least two rolling steps having recrystallization annealing carried out between two rolling steps with a degree of recrystallization in a range of substantially from 95% to 99% at an annealing temperature in the .alpha. range, while the hot-extruded forged part is cold-pilgered in at least two pilgering steps, with a recrystallization annealing carried out between two pilgering steps with a degree of recrystallization in a range of substantially from 95% to 99% at an annealing temperature in the .alpha. range.