Heating Element
There are three things that need to be considered from an engineer's standpoint with respect to the heating elements. The three things are:
The resistivity of the element is very important because the heat given off (power) will be determined by the equations:
Where i is the current, R is the resistance, r
is the resistivity, 
is the length of the wire and A is the cross-sectional area. Since the current put through the wire will be a lot more difficult to change, r
becomes an important factor. Also, having thin wires will help us increase the power.
Oxidation properties are important because this will cause defect motion changing the properties of the metal (specifically resistivity and ductility).
Ductility is important if the wire is kept within the elastic region of the stress-strain curve. If the wire is brought outside of this region, then fatigue will become a factor. It would be best in this situation to use a material that will be within the elastic region.
Nickel and iron alloys will be the primary focus of our search. Nickel alloys will be looked at for their high resistivity properties, while Iron alloys will be looked at for their low cost.
Another important factor to consider is a thin insulation for the wire. A thin insulation is needed to prevent shorting and to protect the wire from moisture, yet it should not hinder the transfer of heat from the wires.
References:
Interview, John VanderSande. February 27
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