Hard Drive Actuator Motor Magnets

Hard Drive Actuator Motor Magnets, Hard Disk Drive Magnets, Hard Drive Magnet Assembly, Hard Disk Actuator Magnet, Head-Actuator Motor Magnets

Hard Drive magnets account for 10% of all the neodymium produced and over 1 million Hard Drives are manufactured every day. It is estimated that over 12 billion have been manufactured to-date.

50% of the world’s neodymium magnets are currently used in computer hard disk drives (HDD) with each HDD typically containing two magnets. The magnets are used in the actuator – a device which moves the actuator arm on the tip of which is the head which reads and writes data to/from the ultra-delicate platters. Driving the arm using magnets means that mechanical wear and tear is not an issue – unlike old-fashioned stepper motor powered hard drives.

Permanent Magnets / Nickel plated neodymium magnets from a hard disk drive.

There are only a few naturally-occurring materials that are magnetic by themselves, without electricity being applied to them to make them into electromagnets. One of them is lodestone. It is actually made of magnetite, but not every piece of magnetite is a lodestone, because not all magnetite is magnetic. To become a lodestone, magnetite has to be magnetized first.

We do not know for certain what magnetizes lodestone in nature, but some believe that it is magnetized by lightning, because lodestone is found closer to the surface of the Earth, while magnetite can be found buried deeper. These days, permanent magnets that we use are most often made of alloys. The most strong magnets are made of rare earth metals like neodymium (Nd2Fe14B), or less strong magnets are made of ceramic / ferrite magnets.