Analysis Of Multi-physical Fields Coupling Characteristics Of The Gas Film In TFC Magnetic Head Disk Interface

In order to meet the market demand for high-capacity, high-density storage and high stability of magnetic storage media, more and more attention has been focused on the study of hard drives as the the storage medium. The operating characteristics of the head disk interface are the key influence factors on the capacity and stability of magnetic storage, if the gap of head and disk is a few nanometers, the gas film is on the combined effects of multiple physical fields, such as the temperature field, the fluid and displacement field. The study of head disk interface, the gas film, and the hard work face features is important to improve the head flying stability and structural design.The object of this study is the head disk interface with plate head and the negative type head, the effect of static and dynamic characteristics of head disk interface were analyzed based on multi-physics coupling. To change the pressure distribution on surface of the head and improve the stability of the hard disk, the head on the gas surface is etched by different shapes, they have different influence on the pressure. It is purposed to study the stability of different type head on mutative working conditions, and provide reference for the design of head slider and increase storage density hard disk.The heat transfer model of head disk interface is established based on the heat conduction and convection theory to research the temperature distribution, and then analyze the impact of the head slider etching trench on the temperature distribution. The head thermal stress and thermal deformation are analysed by considering the material properties of linear expansion, and the influence of operating parameters such as the heating power, flight speed of the head on the heat deformation is studied in this work.The Reynolds equation is modified based on the aerodynamics theory by considering the change of the mean free path, density and viscosity of the air molecules on narrow gap. Analysis the pressure distribution of the head disk interface on the multiple physical coupling effect of temperature, fluid and displacement fields, and the study the pressure distribution on sliders woth different etching groovies.The influence of the slider etching groove on the stress, torque and force point position are researched based on the COMSOL Multiphysics, analysis the influence of the parameters on mechanical properties to provide theoretical support for the head slider design such as disk head relative flight speed, flight altitude, pitch angle and the heater power head.This work studies the relative vibration of the head and disk and the swing pitch angle at the air bearing surface pressure and cantilever systems, analyze the impact of the suspension system’s parameter and the etching trenches on the dynamics of the head slider, this work provide theoretical foundation for the design of suspension system and slider.