工具機主軸的高速化是精密製造發展的重點，在高速運轉的主軸使用液靜壓軸承時會產生大量的熱以及剛性下降等缺點，而液動壓軸承在啟動與停止時極易產生磨損，兩者的發展皆受到限制。為此本研究發展液動靜壓混合軸承來解決這兩種軸承的缺點。本研究探討在四油腔液靜壓軸承之油腔出口處放置多孔材料之瓦片使軸承同時具有動壓與靜壓時之性能表現,以適應不同轉速下之軸旋轉之各物理現像。
本研究以不同材料、製程、顆粒大小的多孔材料製作多孔瓦片,計算其滲透率並且與實驗結果作比較，將量得之參數進行多孔瓦片靜壓軸承的CFD分析;並且開發軸承之製程實際打造具多孔瓦片靜壓軸承。其性能表現則是放在本研究自行開發的量測平台加以驗證。

High rotating speed spindle of machine tools in precision manufacturing is a very important part of machine tool. But heat generation and stiffness decline when the spindle using hydrostatic bearing at high speed are important factors on spindle design. In another way, hydrodynamic bearings may be used in spindle, however, at start-up and stop situations, the bearing pad contacts with shafts which easily cause wear and to make the spindle loss its precision. There are limitations to both types of the bearing. This study improved the four pockets hydrostatic bearing by adding a porous material pad at the opening of chamber of the traditional hydrostatic bearing. This design attempts to make the bearing have both dynamic and static effects at different rotating speed.
In this study, porous pads of different materials, process and powder sizes as are tested. The results of CFD results of the permeability of the the pad are compared with the experiments. The permeability of designed porous pad of our hydrostatic bearing is taken as a parameter in CFD analysis of this present design. The processes of bearing production are developed to produce a Porous Hydrostatic Porous Bearing prototype which was placed on the platform designed by this study to measure their performance.

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