Method for locking a nut made out of a material with a low plastic deformation capacity

The invention relates to a method for locking a nut (48) with an inner thread, in which: the mechanical tensile strength (Rm) and yield strength (Re) of the material constituting the nut are determined according to temperature, an optimal heating temperature (7; 12) is determined, at which a maximum of a relative plastic interval of the material is reached, said relative plastic interval being defined by the formula (Rm-Re) / Rm, a maximum heating time is determined, above which the nut presents the risk of deterioration of its microstructure and/or of its initial mechanical strength, the nut is heated to a temperature substantially equal to said optimal temperature and for a heating time of less than said maximum time so that the initial microstructure and mechanical strength of the material constituting the nut are preserved, a body (47) of the nut is deformed locally by bending. Such a method enables deformation to be more easily applied to the nut without the risk of springback or of breakage of the mater