Abstract: The present invention relates to a method of manufacturing tubes for a nuclear fuel element sheath, comprising a plurality of successive cold rolling and annealing steps including a final .beta. phase heat treatment consisting of maintaining said tube at a temperature between 950.degree. C. and 1250.degree. C. for a time duration sufficient for obtaining a homogeneous .beta. phase within and throughout the whole thickness of said tube, and rapidly cooling said tube to ambient temperature for retaining said .beta. phase throughout the whole thickness of said tube during subsequent cold processing steps including final cleaning of the tube.