Gas-liquid film lubrication for flying head slider with nanometer spacing by the multi-scale approach

1)针对具有超薄润滑膜的近接触磁头/磁盘界面系统的分析与设计，提出了一种新的球面与平面界面模型。通过考虑超薄液面的不稳定性，得到了弯月面成形时的间距。通过超薄膜分离压力和拉普拉斯压力的平衡，得到了半月面的曲率半径和半月面断裂处的间距。固体的变形假定为Hertzian，并考虑了表面不接触时多层间的范德华力。2)数值计算了考虑极性端基影响的超薄液膜表面的变形特性。3)利用新修正的范德华力方程，数值分析了超小间距飞头滑块的静、动态特性。为了更准确地计算，采用了三次内插传播(CIP)方法。4)为了研究接触角对液体半月面动态特性的影响，接触角由排油剂的浓度控制。

In this research project, four researches are planned and executed ; 1)for the analysis and design of the near contact head/disk interface system considering the interactions between a head and a disk with an ultrathin lubricant film, an interfacial model between a sphere and a plane was newly proposed. The spacing at the meniscus forming was obtained by considering the instability of the ultrathin liquid surface. The radius of curvature of the meniscus and the spacing at the meniscus break were obtained by the balance of the disjoining pressure of the ultrathin film and Laplace pressure. The deformation of the solids was supposed to be Hertzian and the van der Waals force between multilayers was also considered when the surfaces do not contact with each other, 2)the deformation characteristics of the ultrathin liquid film surface considering the effects of polar endgroups were calculated numerically, 3)by the use of the newly corrected equation of the van der Waals force, the static and dynamic characteristics of the flying head sliders for ultra small spacing were numerically analyzed including the van der Waals forces. The CIP (Cubic Interpolated Propagation) method was adopted in order to calculate more accurately, 4) for the investigations of the effects of the contact angle on the dynamic characteristics of the liquid meniscus, the contact angle was controlled by the concentration of an oil repellent.