process for the manufacture of bandkernen from an alloy consisting of 45 - 50 wt nickel and the rest mainly iron.

摘要

An alloy comprised of 45 to 53 wt. % Ni with the remainder iron, and including small amounts of deoxidizing and processing additives is worked into a 0.01 to 0.1 mm thick tape, wound to form a tape core and is then subjected to a final annealing for at least one hour at a temperature of at least 900 DEG C. and thereafter is subjected to a tempering in a magnetic cross-field (i.e., the magnetic lines of force are applied in the plane of the tape perpendicular to the rolling direction thereof). The process provides high impulse permeabilities at induction rises of 1T or larger within the so-processed tape cores. Particularly high impulse permeabilities are achieved in instances where an anisotropic structure with a privileged grain direction 001 in the rolling direction is generated in the tape material via heating and final deformation before winding into a tape core and via a final annealing after winding of the tape core. The so-produced tape cores are useful in various electrical applications, particularly in pulse transformers and thyristor choke coils.