Geography of a Hard Drive.

Hard drives are found in almost every computer / laptop now-a-days. Hard drives are a way of storing data, so if we didn't have a hard-drive, we probably wouldn't be able to have computers without paying big bucks for them. I say this because there are now SSD's, but they tend to be much more pricey than the standard hard-drive.

Two main manufacturers of hard-drives are Western-Digital and Seagate. They are both similar and you can't really change how a hard-drive word like you can with a motherboard. Some variables can include however, disk speed, disk storage size, and physical size. WD have different hard-drives such as the WD Blue, the WD Black and, the WD Green.

It takes some time to make one hard-drive. Firstly, the materials are collected. The materials used are, silicone, platinum, aluminium and ruthenium. Some of these materials are mined in South Africa in the Bushveld Complex. From these materials, we will eventually make a functioning hard drive.

The aluminium is firstly cast in to a large blank. The blank ingot is long and cylindrical is size, and it can weigh up to 27 tonnes. It gets heat treated, hot rolled and cold-rolled, to the required size, just enough to keep the disk stable at high speeds. These are produced to a medium finish, which isn't nearly good enough. The blanks are then ground to a high finish using fine stones that are made of PVA. A coating made of nickel and phosphorus. Then the disk with the coating is sanded down to 0.0000001mm. This is 450 times smaller than what is required. This will be upped to 0.0000004mm. It is then cleaned to get rid of any contamination. They use a cloth, but they only press is gently against the disk, as the layer of NiP is so thin. An under-layer of magnetic material is then applied, using materials such as cobalt, iron and nickel. This help separate the disks, using helium, and ruthenium. Then, a lot of odd elements and materials are added to the disk. A diamond like protective overcoat is applied to the disk, only 2nm thick. It's applied with an ion beam. Lubrication is added and the final stage of testing begins. The disks are then stacked, and the hard drive is ready to use.

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