Hard drive data recovery: can you recover data from a scratched platter?

Recovering data from damaged platter has always been challenging since a platter is where data in your hard drive are stored. Damage to the platter literally means damage to your data. But is it possible to salvage files from a scratched platter?

what are the causes of scratched platters?

A normal hard disk platter looks smooth as a mirror, its the magnetic surface been divided into sub-micrometer-sized magnetic regions, each representing a binary unit. 

Scratches on a platter destroy magnetic regions along with data within them, which causes corruption of files.

The most common cause of a scratched platter is the read/write head failure. Under normal working condition, the magnetic head floats above the spinning platter with a “flying height” as small as 3 nano-meters. It leaves the platter and goes back to its rest position when power is down. But a sudden motion of the disk may cause the head unable to maintain the floating position and crashes into the platter. 

Besides, a defective head is also a possible cause of platter damaging.

Can you still recover data from scratched platters?

Whether you can recover data from scratched hard drive or not depends on the scratches.You may send your hard drive to a professional data recovery company to have it fully examined, because to open up a hard drive requires a dust- and static-free clean laboratory. 

If there are very little circular marks, most data can be recovered by reading around the scratches. But do expect some degree of data loss. However if the platter is severely damaged with wide path of scraps, no current data recovery technology can restore the lost data. 

Don't take unnecessary risks by attempting to swap a new head to an already scratched platter. It can be both difficult and risky, as the uneven surface can cause the head to deteriorate faster which in return would cause further damage to the magnetic data. 

To minimize loss, it is rather important to have trained and experienced experts to look into your hard drive, preferably at the first sign of damage(suspicious clicking or screeching sound).