PURPOSE: To attain a junction applying the glass melt-sticking without deteriorating the characteristics of an amorphous metallic magnetic material, by melting instantaneously a glass rod of an adhering groove by the laser light for junction of core blocks.

CONSTITUTION: A pair of core blocks 6 and 6' are butted to each other by means of a tool 11 and pressed properly. Then a glass rod 12 having a low softening temperature is put into an adhering groove 5. The laser light 14 is irradiated to the rod 12 through a condenser lens 15 to heat up the rod 12. Thus the rod 12 is instantaneously melted and therefore the laser oscillation is quickly stopped. Then the blocks 6 and 6' are permeated with the glass 12 to join them together. It is required to transmit the heat only to the area near an adhering groove 8 for blocks 6 and 6' since only the rod 12 is instantaneously heated and melted. This minimizes the effect of heat on the magnetic characteristics.