Patent ID: 7387693

Claim:
A method of altering the resistance of a length of a metal wire having a length L and having a first end and a second end, the wire having a room (ambient) temperature resistance of R ohms, the method comprising the step of applying to the ends of the wire a DC voltage V volts at a current of I amps according to the formulae V=R*I ; and I =√( P/R ) where R is the resistance of the wire at room (ambient) temperature t; P=Q/T where Q=m*cs*Δt where m=the total mass of the wire derived from the formula m=ps*Vc; ps is the density of the wire; Vc is the volume of the wire; cs is the specific heat of the wire; Δt the difference in temperature between the room (ambient) temperature and a temperature selected above ambient that is less than the destruction temperature of the wire; and T is the time in seconds for which the current I at the voltage V is applied; whereby after said application of voltage and current, the resistance of the wire when compared with the initial resistance R is found to be reduced when the first end is connected to the positive pole of a DC source and the second end is connected to the negative pole of the DC source; the resistance of the wire is increased when the first end is connected to the negative pole of a DC source and the second end is connected to the positive pole of the DC source.