I have both items in my hand right now. A former question about hard drive operation created several responses saying stainless steel is magnetic and/or my information was wrong. My information comes straight from the guts of a hard drive. Can somebody explain what I am overlooking about this situation? Or why my information is wrong?
Stainless is made from steel and nickle ,and the better quality id non magnetic. If u are going to buy a set of spoons and knives take a magnetic and u can find the highest nickle.
Back in the 1960's, when hard disk platters were first being manufactured, it did not take long for manufacturers to realise that the platter itself needs to be constructed from non-magnetic material, otherwise residual magnetism in the platter will affect the data recorded on the surface. So, as far as I know, most platters are actually aluminium, not stainless steel. As LeAnne has said, information is only recorded on the surface, ferrite based material, not on the disc itself.
The thin film layer of magnetic material is so minute compared to the mass of the platter that any attraction would be undetectable with a hand held magnet - however, you can rest assured that there's no more valid data on it if you try. In contrast, the magnetic properties of a piece of Mylar tape are evident because the tape is so flimsy and light it immediately reacts to a magnetic field placed near it.
