Western Digital announces 18TB, 20TB hard drives

Storage giant Western Digital has crowed of another breakthrough in areal density for magnetic storage, announcing that it will launch 18TB and 20TB 3.5" drives in the first half of 2020 - though is aiming them at data centre users.

Areal density - the amount of data you can cram onto a given square inch of a platter - is a continuing battleground for storage manufacturers. A range of novel technologies have been introduced in an attempt to shove increasing quantities of data into a fixed volume, from shingled magnetic record (SMR) to heat-assisted magnetic recording (HAMR) - and even replacing the air inside a hard drive with helium, as a means of reducing drag and improving heat transfer. Like the march of Moore's Law on the CPU side, increasing areal density gets increasingly challenging over time - but Western Digital isn't giving up.

The company's latest announcement details a new pair of Ultrastar 3.5" hard drives which pack in the highest amount of data yet: 18TB and 20TB. The former uses conventional magnetic recording (CMR); the latter boosts capacity still further by using shingled magnetic recording (SMR), a clever means of increasing storage capacity by borrowing a few tricks originally developed for NAND flash storage devices. Both use energy-assisted magnetic recording technology (EAMR), a variant of heat-assisted magnetic recording (HAMR), while including an impressive nine platters per drive.

'Western Digital continues to innovate to deliver efficient, purpose-built storage with excellent TCO [total cost of ownership] with the optimal combination of industry-leading areal density, mechanical innovations and materials advancements,' said Christopher Bergey, senior vice president and general manager of data centre devices at Western Digital. 'Leveraging our success in bringing energy-assisted recording to market with our expertise in mechanical design, we can deliver this scalable HDD platform with significant capacity increases to our customers, particularly in the transition from 14TB to 18TB.'

Pricing for the new drives isn't yet available; Western Digital has confirmed it will be sampling the CMR variant in 16TB and 18TB capacities plus the 20TB SMR version to selected customers by the end of the year, with a view to commercial availability in the first half of 2020.