Cathode head having filament protection features

A method for manufacturing a cathode head assembly, the method comprising:

• defining a recess within a cathode head;
• affixing an insert within the recess, the insert comprising a refractory material;
• after the insert has been affixed within the recess, forming a slot within the recess such that a portion of the slot is defined within the insert;
• and
• attaching a filament to the cathode head such that at least a portion of the filament is disposed within the slot.

An x-ray tube, comprising:

• an evacuated enclosure;
• a cathode assembly contained in the evacuated enclosure, the cathode assembly including:
• a cathode head having a head surface, the head surface having a recess defined therein;
• an insert defining a portion of a slot, the slot being at least partially positioned within the recess, wherein at least a portion of the insert defines a protective surface, the protective surface being comprised of a material that acts to substantially prevent fusing of the filament to the protective surface when the filament contacts the protective surface;
• an electron-emitting filament partially disposed in the slot;
• and
• an anode contained in the evacuated enclosure and positioned to receive electrons produced by the filament.