Often forensic & data recovery specialists, reduce their sales approach to cheap sales tricks with claims that they have acquired/developed machines capable of reading SATA RAID servers and conventional hard disk platters without changing the head. Unfortunately this rhetoric is being repeated by few reputed companies. Little did they know, the US Pentagon has had since 9/11 a live advert on their website seeking clarifications on such "machines or technologies".

Only a month ago the US Pentagon have decided to cancel the ad as there was not a single reply for 5 years!!

A magnetic disk/ platters is a circular aluminum disk with surface coated with chrome oxide based coating for the sole exception of the parking zone, if it is present. In fact, high precision of disk surfaces and the heads causes them to "stick" to each other because of molecular attraction forces. To prevent that effect, manufacturers use special laser serrations in the zone of contact between drive heads and disks.

The disks demonstrate specific magnetic properties owing to their chrome oxide based coating (magnetically active substance) or cobalt layer applied using vacuum deposition. Such coating is characterized by high hardness and much greater wear resistance compared to previous models coated with a layer of soft varnish based on ferric oxides which could be easily damaged unlike modern coatings.

While, sales myths are circulating among data recovery sales representatives in the USA & Western Europe, advanced data recovery technologies have predominantly been emerging from the former Eastern Block countries & India rather than Western Europe and America.

However, new hardware industry is being rapidly developed in mainland China, with the scope for further advancements within the data recovery technology fields emerging from China is expected. This is due to the anouncement that the investment in the hardware manufactring industry will be trippled.
http://www.unirecovery.co.uk/disk.php