Although it is undeniable that the storage capacity of mechanical hard disks has been slowly improving, and now it has achieved 20TB on the market, but at the recent IEEE technical conference, expert Tom Gardner sharply pointed out that the unit storage density of mechanical hard disks has been reversed for a long time in the past few years.
It is clear from the chart below that the capacity density of the current mechanical hard disk is stuck at 1.1Tb/inch, which is lower than the highest level in the industry in 2017, 1.3Tb/inch, and also lower than 1.2Tb/inch 7 years ago, that is, in 2015.
Some friends may wonder why the total capacity is increasing because the density of platters is low, because the number of platters has increased, and 20TB hard disks have been encapsulated with 10 discs.
For consumer-grade hard disks, the size of the three dimensions has standard requirements, that is, the increase in the number of platters will lead to narrowing of the gap, heat and other issues are more difficult to control, so improving the density of platters is still a more meaningful research direction.
In fact, the original intention of technologies such as SMR (Stacked Tile Magnetic Recording) and HAMR (Thermal Auxiliary Magnetic Recording) is to improve the disk surface storage density.
According to Seagate, its HAMR hard drive can create a storage density of 1.5 to 2.6Tb/inch, and achieve 6Tb/inch by 2030, thus achieving a 100TB 3.5-inch hard disk.
