Melchior tape, Dnipropetrovsk region.

Copper tapes are thin strips, made of copper alloys and having a rectangular cross-section. They are produced in a cold-rolled way, and delivered in coils or rolls. Copper grades M1f, M1r, M1, M2r, M2, M3r, M3 are used for production. The number in the designation of the alloy indicates the copper content - the higher the number, the higher the number. The letters "r" and "f" reflect another important characteristic - the reduced oxygen content, which impairs the following technological properties:
• corrosion resistance;
• plasticity;
• thermal conductivity;(//tractor-service.com)
• solderability;
• weldability.
However, a decrease in the oxygen content leads to a decrease in the electrical conductivity of the copper alloy. The tape used for the production of power capacitors and current-carrying windings of transformers can also be made of M1E copper.

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