Is it possible to give a damage of about can not be restored to the HDD with the power of neodymium magnet?

byPatrick Lindenberg

Data that should have been deletedFree software that can be restoredThere are various services and services, among othersYou can restore deleted files with just 3 clicksThere also exists. In order to delete the file perfectly to the level which can not be recovered even with such software,Neodymium magnetThe user who carried out the experiment described the details.

Hard Drive Destruction
https://www.kjmagnetics.com/blog.asp?p=hard-drive-destruction


Especially strong neodymium magnets among permanent magnets cause magnetic defects when approaching credit cards and also damage VHS data. "If there is so much power, it is possible to damage the data in the HDD which is magnetic media as well as VHS?" The question that sells neodymium magnetsK & J MagneticsIt was experimented and solved it.

In K & J Magnetics, in order to investigate in real time how the neodymium magnet affects the data in the HDD, the CD bootable OSDamn Small LinuxPrepare an environment where there is no problem even if there is an influence on HDD by using.

And IBM made HDD (30GB 7200RPMIDE) Was written 1000 times repeatedly as "K & J Magnetics is your source for the world's strongest magnets."text fileThousands of the HDDs were saved, and the HDD itself was interleaved with a neodymium magnet, so we examined how much the text file was damaged.

At the time of verification, as shown below, on both sides of the HDDNeodymium magnetHas been pasted. In experiments, we used neodymium magnets of various sizes, with neodymium magnets in close proximity to the upper end of the rotating head of the HDD with the HDD running.


The result of the experiment was unexpected, and even if using a neodymium magnet it was impossible to damage the data in the HDD at all. The following image is an image image when neodymium magnets are attached to both sides of the HDD and shows where the strongest magnetic field is formed in the HDD. K & J Magnetics predicts "Even if the inside is shielded, it will have some influence on the outermost disc", HDD's platter should have passed under the neodymium magnet with the momentum of 7200 revolutions per minute , It never caused an error.


However,RY 04 Y 0 DIAIf you attach a strong magnet like this, it is said that a mechanical fricative sound was thought to have occurred due to inclination of the internal platter. However, because the purpose of K & J Magnetics was not to physically destroy HDD, it seems that we did not do actively destroy HDD by moving magnets.

Older type magnetic recording media such as VHS and credit cards can be destroyed with neodymium magnets, but theseCoercive forceIs lower than the magnetic field created by the magnet,500 to 1000Oerstedt(Oe) degree. On the other hand, the coercive force of the HDD is1250From Oe2500It seems to be high with Oe, and it seems to have a higher coercive force as it becomes the latest one.

Data erase service of HDD etc is to erase data by using strong degaussing device or physically destroying HDD. And as the coercivity of the HDD increases, physically destroying the HDD is becoming a common way.

A movie that thoroughly destroys with a drill or a polishing machine so that it can not restore confidential information-packed HDD - GIGAZINE


Although K & J Magnetics did not test all combinations using magnets, it seems that even one nearest character in the file could not be changed even with a neodymium magnet, "If you use a neodymium magnet you can erase all data" He seems to have arrived at the conclusion that the idea is a mistake.

From these results, it is recommended to use in-HDD data erasure software to write random data multiple times when discarding still operational HDDs. It is recommended that "Darik's Boot and Nuke"Eraser"KillDiskThree. Moreover, since it is not possible to execute these software when HDD does not work, it is considered that it is the best way to physically destroy HDD.

In addition, this survey investigated "Whether data in HDD can be completely erased with neodymium magnet", it did not come true, but HDD will be damaged if neodymium magnet is on HDD side There is no doubt, "K & J Magnetics should warn you," You should leave the neodymium magnet away from the HDD. "