Destroying an internal hard drive

Salt water doesn't destroy the data on the platters. It gradually degrades the quality of the actual storage layer on the platter, but that goes very slowly (think weeks).
It will damage the electronics and the read/write heads very fast (minutes), but the data is still there and can, fairly easily, be retrieved by a specialist.

Just run a 1-pass wipe with random garbage over the drive or put a drill through the drive. That does far more damage.

Please note:
People still claim that a single pass overwrite isn't enough and that you need to do it at least 3 (or 7, or 35) times.
That used to be true for old disk technology, with relatively low-density storage, but for anything younger than 20 years a single pass is sufficient to make reading any worthwhile amount of data next to impossible.
Only the CIA and similar organizations have the resources to attempt such recovery and even for them it is extremely difficult to do.

Tonny

Posted 2020-01-30T16:14:26.333

Reputation: 19 919

Really salt doesn't corrode the platters? – Moab – 2020-01-30T17:25:05.967

@Moab Eventually, if you're willing to wait a couple of weeks. These platters are surprisingly resistant against corrosion. Harddisks (except the helium filed ones) are not air-tight. Humidity and minor amounts of contaminant from the air does get in. (Most drives actually have a breathing-hole to equalize inner and outer air-pressure). Still they are good for years. The magnetic top layer of the platter is actually a mix of several metal-oxides, aka rust, so they are already corroded. The salt ions will interact with the oxide-ions and degrade that layer, but it is quite a slow process. – Tonny – 2020-01-30T23:09:08.620

@Moab Extended the answer a bit to clarify this some more. – Tonny – 2020-01-30T23:11:59.807

That is one way. Water has to seep into the enclosure. I just drill a couple of holes through it. – John – 2020-01-30T16:18:16.927

1An easier method would be to simply drill through the platters after running a 5x wipe with random characters... keep in mind salts are only effective if water has evaporated from the platters, leaving salt crystals, and the platters were not cleaned prior to power on and head activity (i.e. simply submerging the drive in a salt solution and leaving the drive itself undamaged would not 100% guarantee the data isn't recoverable; there are multiple companies that specialize in data recovery for drives submerged by hurricanes and floods.) – JW0914 – 2020-01-30T16:23:05.817

1Pop a nail through it and throw away. – NiallUK – 2020-01-30T16:37:00.913

Destroying an internal hard drive

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