Metal foil resistor. Chapter 3. Effect of temperature on metals and alloys.

Alloys for electrical resistance.
Chromium nickel alloys are characterized by having a large electrical resistance
(about 58 times that of copper), a small temperature coefficient and high
resistance to oxidation. Examples are Chromel A and Nichrome V, whose
typical composition is 80 Ni and 20 Cr, with its melting point to 1420 ° C.
When you add a small amount of iron to nickel-chromium alloy, are becoming
more ductile. The Nichrome and Chromel C are examples of an alloy containing
iron. The composition typical of Nichrome is 60 Ni, 12 Cr, 26 Fe, 2 Mn and
Chromel C, 64 Ni, 11 Cr, Fe 25. The melting temperature of these alloys are
1350 ° and 1390 ° C, respectively. In the figure are variations of resistance with
temperature of these alloys