Common Physical Failures in Hard Drives
One of the most common physical causes of data loss occurs at the head assembly level, where the read and write mechanisms are located. This section is the most crucial part of the hard drive because it’s not only the fastest-moving but also the most delicate.
Fortunately, one area that we don’t need to worry as much about nowadays is the spindle. Manufacturers have continuously improved this component, and as a result, failure rates for the spindle have consistently dropped in recent years.
Unfortunately, the read/write heads remain at risk. The heads are mounted on tiny sliders that hover just a fraction above the platter surface—typically less than the width of a human hair. They are responsible for reading and writing data as the platters spin at high speeds. Any impact, such as the drive being dropped, shaken, or bumped, can cause the heads to make contact with the platter, leading to damage. This often results in a “head crash,” where the head physically scratches the platter, rendering data inaccessible or causing permanent damage to the drive.
Electrical Damage
Hard drives can also suffer from electronic failures. Spikes in the mains voltage can travel through the HDD’s printed circuit board (PCB) and affect the magnetic media on the platters, leading to magnetic damage, also known as media corruption.
Water Damage
Another common type of damage is water exposure. Hard drives are designed with a breathing hole and filter to equalize pressure inside and outside the drive. If a drive is submerged in water for only a few seconds, it usually doesn’t cause major issues. However, if the drive is submerged for a longer period, water can seep inside, since the drive is not fully sealed by design.
Fire Damage
Fire is another physical cause of failure we often see. Short exposure to temperatures around 100°C may not cause significant damage, but prolonged exposure to temperatures around 200°C can result in data corruption. Exposure to temperatures above 300°C can even cause the electronic connections to de-solder, and since HDDs and platters are often made of aluminum, they can warp.
An often overlooked issue with fire damage is that firefighters typically use cold water to extinguish the flames. Not only does this introduce water damage to the drive, but the extreme temperature shift can cause further warping and extend the damage.
Is Data Recoverable from These Types of Damage?
Fortunately, in many cases, data recovery is possible, but it requires the expertise of a professional who knows how to retrieve the data without causing further (and possibly irreparable) damage.
Several factors determine whether recovery is possible. For example, recovery may depend on the severity of the crash. If the electronics are damaged, repairing them may allow the drive to function well enough for data recovery. The duration and extent of exposure to fire or water also play a critical role in the recovery process.
