В стандарте ISO по выбору сварочных материалов даётся три варианта определения данного термина:

heat
〈open hearth, electric arc, basic oxygen, argon-oxygen processes〉 for consumable inserts, solid wires, rods and strip, core wire for covered electrodes, and the sheath (strip or tubing of tubular cored electrode wire and rod), material obtained from one furnace melt, where slag-metal or gas-metal reactions occur in producing the metal
2.4.2
heat
〈induction melting in a controlled atmosphere or in a vacuum〉 for consumable inserts, solid wires, rods and strip, core wire for covered electrodes, and the sheath (strip or tubing of tubular cored electrode wire and rod), an uninterrupted series of melts from one controlled batch of metals and alloying ingredients in one melting furnace under the same melting conditions, each melt conforming to the chemical composition range approved by the purchaser of the material (i.e. the producer of the welding consumable) where significant chemical reactions do not occur in producing the metal
2.4.3
heat
〈consumable electrode remelt〉 for consumable inserts, solid wires, rods and strip, core wire for covered electrodes, and the sheath (strip or tubing of tubular cored electrode wire and rod), an uninterrupted series of remelts in one furnace under the same remelting conditions using one or more consumable electrodes produced from a heat, as defined, each remelt conforming to the chemical composition range approved by the purchaser of the material (i.e. the producer of the welding consumable) in processes involving continuous melting and casting

Я в совершенном ступоре по поводу соответствующего термина на русском языке!

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