Then a miracle occurs.

In Sidney Harris’ book of cartoons, one shows two scientists staring at a blackboard filled with the steps of a complex reaction. One of them is pointing and saying “I think you should be more explicit here in step two.”  That step is: Then a miracle occurs.

Most scientists don’t like depending on miracles, so I’d like to talk about some of the basic science that give reasons why the ferromagnetic generator is more than hoping for a miracle. First: The Curie Point.

My website contains a more detailed explanation of the Curie Point—and most any physics book will do an even better job. But here is a simple run-down.

In 1895 Pierre Curie discovered that for any ferromagnetic material, (6 elements and associated alloys) there is a temperature at which it stops being what we call magnetic. Ferromagnetism is created by a special form of electron interaction called exchange coupling that takes place between atoms sitting next to each other in the crystal.  At the Curie temperature, the strength of the exchange coupling equals the energy of the thermal agitation.  Above that temperature, the coupling comes apart and the sample’s overall magnetism disappears.  Not understood in the 1890’s was that exchange coupling is a quantum effect. That means the switch from ‘magnetic’ to ‘not magnetic’ occurs over a narrow band of temperatures.

Pure iron, whose Curie Point is 766°C, retains considerable magnetic properties even at temperatures as hot as 650°C. Yet a few degrees above 766°C all of its ferromagnetic properties disappear.

Here is a graph I drew that approximates this effect in iron:

The red line shows the actual way the magnetic properties are lost by an iron sample being heated to its Curie Point. The green line shows the way the loss would occur if exchange coupling was a classical effect. Fortunately for the ferromagnetic generator, quantum linking allows the sample retain considerable magnetism almost up to its Curie Point.

The vertical scale on that graph is permittivity (how many lines of flux will go through the iron rather than air.)  So the bottom represents air.  Normally, the magnetic lines of force prefer transformer iron around 7000 times more than air.  That’s the point where the red and green lines touch the left side of the graph. For our generator, note that even at high temperatures, the magnetic lines of force will still prefer to go through the iron sample rather than the air.

So Air = 1 and that means transformer iron carries 7000 seven thousand times more magnetic lines of force than the same physical space if it contained air.  Other metals and alloys have different permittivities:  Cobalt = 250, Nickel = 600, Mild steel = 2000, regular Iron = 5000.  There are hundreds of magnetic alloys, here are a couple of the impressive ones: Permalloy = 100,000.  Supermalloy = 1,000,000.

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