本論文探討的是受擠壓於平板間的液體，其液體的黏度變化與固液界面親和力大小的關係。本研究液體採用的是正十四烷(C14H30)及水，下試件選擇的是高定相熱解石墨及雲母，特點在於用液動壓的模型求出液體受壓時的黏度變化，並針對黏度變化差異進行討論。
　　實驗部份，以奈米壓痕機的球型壓頭接近下試件-雲母或高定相熱解石墨，兩者間距中為實驗液體-正十四烷或水，以此得到整個過程中負載-壓深關係圖。理論部份，先以赫茲接觸理論判斷出液體受擠壓產生抵抗力的區域，分析此區域壓頭上的壓力分布，將壓頭徑向方向微分成小區域，每個部分以平板間的液動壓模型描述之。液動壓模型中包含間距及黏度函數，間距分布方面，由機台紀錄之位移減去壓頭與試件的接觸點為球頭中心間距，需再加上球頭幾何關係如圖(2.3.2)得徑向間距分布，並考慮液體產生的壓力場會使下試件變形，吾人利用彈液動理論得到下試件變形場的分布加以修正其間距；黏度函數方面，提出類似高斯分布的模型，特點是描述黏度達極值後會往下降。上述兩函數分布代入液動壓模型可得球頭壓力分布，再用計算其總力與實驗值進行驗證，其誤差值小於1%，使確立黏度模型的可信度。
　　利用接觸角實驗確定四種固液組合的界面親和力大小關係。以同一種液體對於不同試件的黏度變化進行討論，固液界面親和力成為唯一變數，若固液界面親和力越大固體越容易抓住第一層液體分子，造成液體受擠壓而移動時阻力增加不易往兩側排開，直到排開的力大於固液界面親和力時，第一層分子也跟著滑移造成剪應變率上升而黏度下降。由得到的結果可以發現，不論液體是水或正十四烷，對於較親和的固體其液體黏度上升的極值越高、越能承受更大壓力與液體在間距較小時才潰散。

The aim of this paper is to discuss the relationship of the variation of liquid’s viscosity and the solid-liquid absorptiveness, which the liquid is under squeeze between two plates. The equation of hydrodynamics is used to find the variation of the liquid’s viscosity under squeeze. There are four different kinds of solid-liquid combination. n-Tetracane(C14H30) and water are used as the experimental liquids, and mica and highly oriented pyrolytic graphite(HOPG) are used as the specimens.
In nanoindentation, a spherical indenter was moved to approach mica and highly oriented pyrolytic graphite specimens immersed in n-Tetracane and water liquids in order to know the load-depth data.
The area where the liquid under squeeze with repulsive force can be found through Hertzian contact theory. The repulsive force is used to certify whether the calculations result is close. The equation of hydrodynamics includes function of gap and function of viscosity. The function of gap can be known by depth data cut the location of Hertzian contact, the geometric of spherical indenter and the elastohydrodynamic theory as figure (2.3.2). An important part to know the function of viscosity is a Gaussian-like distribution, which its character is that the viscosity goes down when it reaches the maximum value. According to two functions above, the theoretical value of the pressure distribution under the indenter can be calculated. The reliability of the viscosity model can be known when the error of theoretical value and experimental value are under 1%.
Using contact angle experiment, the relationship of interface absorptiveness of four different kinds of solid-liquid combinations can be known. The solid-liquid interface absorptiveness becomes the only variable to variation of viscosity under the circumstance which one liquid combines with different specimens. The friction force increases when the solid-liquid interface absorptiveness enhances because the absorptiveness of the liquids near the solid surface is higher. As the liquid near the solid surface slips, shear strain rate increases and viscosity decreases. For all cases, the tendency of viscosity maximum is consistent with solid-liquid absorptiveness. It implies that strong solid-liquid absorptiveness enhances viscosity, which is helpful for resistance against squeeze out.

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