Is copper or lead able to deflect magnetic fields and do either of these materials become magnetised over time, how well do they actas magnetic field shields?

Lead and Copper can not be set to be magnetized.
Copper however can act as a magnet By flowing an electric current through coil of it. The copper itself isn't magnetized, nor does it retain any magnetic for when the electric flow ceases, it simply conducts the electricity.


Magnetic fields (forces are caused by magnetic fields) cannot be blocked, no. That is, there is no such thing as a magnetic insulator.

A major reason for this has to do with one of Maxwell's Equations:

del dot B = 0

Which implies that there are no magnetic monopoles. That is, where as you can separate electric monopoles (positive and negative charges) such that an E-field never has to terminate on the opposite charge, you cannot do this with magnetic poles. There do not exist any magnetic monopoles. There is no such thing as "magnetic charge." All magnetic field lines MUST TERMINATE on the opposite pole. Because of this, there is no way to stop them -- nature must find a way to return the magnetic field lines back to an opposite pole.

However, magnetic fields can be re-routed around objects. This is a form of magnetic shielding. By surrounding an object with a material which can "conduct" magnetic flux better than the materials around it, the magnetic field will tend to flow along this material and avoid the objects inside. This allows the field lines to terminate on the opposite poles, but just gives them a different route to follow.

You might want to check out:
http://www.lessemf.com/faq-shie.html#Lead-Copper
Which does a good job to answer your question directly.

To build a magnetic field 'shield', you need to construct a Faraday Cage. That's basically a grounded wire mesh container.

copper will conduct a magnetic field
this is how electro magnets are made, by coiling copper wire and inducing EMF throught them
lead will also conduct a magnetic field, but not as well as copper
so neither will deflect a MF
copper or lead will not become magnetized persay, but if it is coiled and has EMF induced it will become a magnet, until the EMF is turned off

if added to neodynium it will because it can hold magnetic segments with the right hand rule.