We work on machines that enable—and, in fact, store— our dreams. For most of the history of rigid-media data storage, those dreams have been kept on thin, round platters of aluminum. Nonetheless, the time may be coming when aluminum substrates join ferrite heads and peak-detection channels as technologies that are unable to provide the means to enable our future aspirations. Ever since the IBM RAMAC disk drive of the mid-1950s, rigid disk drives have used smooth aluminum platters as substrates. In the 1960s, media manufacturers began to coat raw aluminum-alloy disks with a nickel-phosphorus (NiP) layer to obtain a smoother and harder magnetic surface. This formulation became the standard substrate material for all the iron-oxide particulate-coated magnetic-recording media used through the 1980s.
展开▼
