How does a DC current polarize

[jsmith613]

from my understanding polarization is a way of causing objects to be diametrically opposed (North and South poles for example)

What I don't understand is how a DC current polarizes a metal. Obviously for something to be magnetic it MUST be polarized but why does a DC current have to be used, why can't it be an AC current?

Thanks

 

[vebrown]

An AC current when coiled around a magnetic capable material continually switches poles with each repeating cycle. This disrupts the magnetizing process. A DC current keeps the same polarity so that the material can align its atoms and so take on the magnetic property.