[Micele]

Oorspronkelijk geplaatst door six

Exodus negeert vragen die hem niet aanstaan.

En een magnetische steen kan een harde schijf niet wissen.

Denk je.

blz 11

http://www.hgst.com/tech/techlib.nsf...ctional.v6.pdf
Hard Disk Drive Specifications

© 2003, Hitachi Global Storage Technologies. All Rights Reserved.

...
3.2 Environmental conditions and reliability

Table 3.2 Environmental conditions and reliability
Ultrastar 10K300-300 Ultrastar 10K300-147 Ultrastar 10K300-73 Ultrastar
10K300-36
...
Magnetic field 400 micro Tesla maximum
Drawing No. Sheet No. Revision ６
K6610091 11/43 2005/2/23

http://goodsamt.com/resources/magnetism.pdf

Magnets have been known to people forever, however, the use of special rock called Lodestone (it leads or points to the North) to make simple compass goes back to about
1100 A.D. There are reports about Muslim navigators use of compass around 1200 A.D.
Materials that are strongly attracted to magnets are called ferromagnetic materials, and
they include iron, cobalt, nickel, some rare earth alloys as well as some natural rocks like
lodestone. Such materials could be magnetized and act like a magnet resulting in one of
two types of magnets: Permanent (hard) and temporary (soft) magnets.
Magnets are affected by shock, temperature, age, and magnetic fields.
Permanent magnets are classified into the following categories:
1- Rear Earth magnets: they include Neodymium Iron Boron (NIB), and Samarium
Cobalt (SmCo). These are the strongest magnets with strength of about 1 Tesla,
and the hardest to demagnetize, however, their maximum operating temperature is
lower than other magnets.
2- Alnico: Made form Aluminum, Nickel, and Cobalt. They produce a strength of
about 0.15 T. They are least affected by temperature, but easily demagnetized.
3- Ceramic or Ferrite: Very popular, and include flexible magnets, with strength of
about 0.1 T. Not as easily demagnetized, but their strength changes with
temperature.
Cast iron is an example for the material of soft magnets.