奈米壓痕技術(Nanoindentation)在近年來對於量測奈米材料之機械性質已成為一不可或缺的工具，而連續勁度量測法(Continuous Stiffness Measurement (CSM))是利用探針加載的過程當中附加ㄧ微小之週期振動力，得以連續地量測材料之接觸勁度與接觸阻尼。在本文中除了精確的推導黏彈性材料之奈米壓痕理論外，亦針對黏彈性材料甲基丙烯酸甲酯Poly(methyl methacrylate) (PMMA)利用連續勁度量測法量測其動態模數；同時，我們也測得不同振動頻率下的動態模數，並將試驗結果與動態機械分析(Dynamic Mechanical Analysis (DMA))所得的結果互相比較。

Nanoindentation has become an indispensable tool for probing mechanical properties at small length scales. The continuous stiffness measurement (CSM) in nanoindentation is accomplished by superimposing a small oscillation of a fixed frequency on the primary load to continuously measure the contact stiffness and contact damping during loading. In this research, we derived the rigorous theory of oscillatory nanoindentation of viscoelastic solids. We also performed nanoindentation tests using CSM method to characterize the dynamic modulus of Poly(methyl methacrylate) (PMMA). In the CSM tests, frequencies of the oscillating force were varied in a range and the results are compared with known data as well as our own data obtained by DMA test.

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