Thermal Flying-Height Control Sliders in Air-Helium Gas Mixtures

Filling hard disk drives with air-helium gas mixtures instead of pure helium can balance performance improvement, such as reduced power cost, increased capacity and improved reliability, against manufacturing cost increase. A consistent approach is proposed here to investigate the flying performance of thermal flying height control sliders flying in air-helium gas mixtures. It is found that the smallest power required for a designated flying height appears when the gas mixture is composed of about half helium and half air. The proposed numerical approach can also find application in investigating a slider's flying performance in a humid environment.

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