# Maximum magnetic strength achievable

What will be the maximum magnetic strength to which a piece of ferromagnetic substance can be magnetised?

What will the maximum strength possible for a piece of iron?

How would the shape of the ferromagnetic substance affect this strength?

What would be the current needed in the solenoid if this strength is to be achieved?

• For the solenoid part, assume the dimensions and mention them. – karthikeyan May 20 '14 at 14:19

The field at the centre of solenoid is $B = \mu n I$, and the graph in the linked article shows the required values of the product $nI$. For most materials it's some where in the range $nI = 50 - 100$ amp turns per inch.