# magnetising the material using coil

I studied that when alternating current is passed through the coil ,the coil produce magnetic field (primary) as shown in figure,when any conducting material placed near to that field, eddy current is induced on that material and that eddy current produce secondary magnetic field on that conducting material,so

i build a coil ,which wounded over a plastic bobbin,which inductance value is 88mh, to produce secondary magnetic field on some metal when i place near to it .

does this coil produce eddy current only in AC,what happen if i supply DC? what should i do TO make strong secondary magnetic field ?

It comes from Maxwell-Faraday equation: $\oint_{\delta\Sigma} {\mathbf{E}~d\mathbf{l}} = - \frac{d}{dt}~ \int\int_\Sigma \mathbf{B}~d\mathbf{S}$
Magnetic flux $\Phi = \int\int_\Sigma \mathbf{B}~d\mathbf{S}=L~I$.