What are nichelina and kanthalul?
What are nichelin and kanthal?
Nichelin: NiCr alloy, in varying amounts
Kanthal: a FeCrAl alloy, in varying amounts
In the link below, it shows our complete wire resistive, including different types of Kanthal and nichelina: Kanthal wire and Nichelina.
Observe the following:
– Kanthalul A1 (22% Cr, 5.8% Al, remainder Fe) has a melting temperature of 1400 ° C, while the standard type (22% Cr, 4.8% Al, rest Fe) melts at 1300 ° C. Remember, it’s melting temperature.
Punctulmeu of view, is good and Kanthal Standard as well as the type A1. I’d still be curious as kanthalul type AE, which is said “developed to meet the extreme demands in fast response elements in glass and quartz tube heaters top hobs. It has exceptional stability and life form in spirals with large coil diameter to wire ratio “, ie” developed to meet the extreme requirements of rapid response elements in the top of the quartz tube heaters. It has exceptional stability and long life in relation to the wire diameter “
– Nichelina (think “Nikrothal” or “Nichrome” 80 is more popular, 80% Ni, 20% Cr) has a melting temperature of 1200 ° C. I mention this only as a comparison, but as I said above, if kanthalului, the melting point is nonessential for me.
– Nichelina has resistivity less than kanthalului: Nichelina 80 -> 1.09 ohms * mm² / m compared to Kanthal A1 -> 1.45 ohms * mm² / m. Resistant can build larger (in terms of size) for the same ohmic resistance.
– Appears a term – “emissivity” material.
Definition: an object emissivity ability to emit or absorb energy. “Emitters” were emissivity perfect “1”, emitting 100% of incident energy.
Kanthal A1 emissivity is 0.70, while that of Nichrome 80 0.88. For example, emissivity silver is 0.01 (ie reflects and transmits very good, does not absorb – can not be used as a radiator), while the “black body” is 1 (the energy emitted is equal to that absorbed – radiating perfect). That makes nichelina be better than radiating element (resistance in our case) than kanthalul. Energia “absorbed” is the one that turns into heat, our resistances.
Remember, the two most important issues:
1) Al oxide (Al2O3) format kanthalului better adhere to the surface, so it is less contaminant. It is a better electrical insulator (best so for genesis sites) and best atmospheres resistant than carbonated Cr oxide (Cr2O3) nichelina format.
2) Al oxide (Al2O3 or alumina) formed on the surface kanthalului is light gray (if the temperature exceeds 1000 ° C) or darkens as 1000 ° C. Alumina has excellent electrical insulation properties and good chemical resistance in front of many compounds.
Cr oxide formed on the surface nichelinei (Cr2O3) is dark.
=> Kanthalul has 2-4 times longer life than nichelina
=> Nichelinei most important advantage is that it has a high resistance to corrosion at room temperature. Oxide breaks off and evaporates more easily than thicker oxide formed on the surface kanthalului.
Another reason for going only as Kanthal is formed on the surface oxide nichelinei is Cr oxide. He can be multi-valent, and is known (clearly shown) as penta and hexavalent oxides are carcinogenic. Now, higher valence oxides are formed only at high temperatures (from several hundreds of degrees up).