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WD Announces 8TB, 10TB Helium Hard Drives
Lucas123 writes: Western Digital's HGST subsidiary today announced it's shipping its first 8TB and the world's first 10TB helium-filled hard drive. The 3.5-in, 10TB drive also marks HGST's first foray into the use of shingled magnetic recording technology, which Seagate began using last year. Unlike standard perpendicular magnetic recording (PMR), where data tracks rest side by side, SMR overlaps the tracks on a platter like shingles on a roof, thereby allowing a higher areal density. Seagate has said SMR technology will allow it to achieve 20TB drives by 2020. That company has yet to use helium, however. HGST said its use of hermetically-sealed helium drives reduces friction among moving drive components and keeps dust out. Both drives use a 7-platter configuration with a 7200 RPM spindle speed. The company said it plans to discontinue its production of air-only drives by 2017, replacing all data center models with helium drives.
I was also wondering this. Wouldn't nitrogen or argon/neon be cheaper?
The point of using helium is NOT that it is inert, but that it is low density (although the inertness is also nice). Neon is five times as dense and far more expensive. Methane is four times the density. The only gas lighter would be hydrogen. But hydrogen has a nasty habit of migrating through metal, leaking out, and embrittling the metal in the process. Low density gases reduce friction both through reduced mass, and a higher speed threshold for laminar (rather than turbulent) flow. Low density gases tend to also be better heat conductors, helping to keep the disk cool. That is why high density gases, like xenon or sulfer hexafloride, are used in insulated windows.