隨著航空產業的蓬勃發展，為了增加飛行的安全性，對於飛機上的自動駕駛儀的性能要求也逐漸提升，由於自動駕駛儀中連接了許多微機電感測元件，然而在飛機機身中卻有許多高溫環境，如發電機周圍。為了使諧振器仍具有良好的準確度和穩定性，因此必須深入了解在不同溫度下，諧振器振盪過程中，應變場與溫度場不同相位時造成的能量耗散現象。
本研究建立Timoshenko微型樑熱彈性阻尼模型，分析橫向等向性彈性參數: E_p、E_z、u_p、u_z和G_{pz}的影響。分為四個部分討論:第一、穩態分析中了解Timoshenko懸臂樑在自由端端點受到z軸方向向下力時的變形程度，得知厚度方向的楊氏模數(E_z)與蒲松比(u_z)影響很小，第二、單層熱彈性阻尼分析中主要討論另外三個彈性參數帶來的影響影響，第三、雙層熱彈性阻尼分析中討論橫向等向性影響因子在不同的體積分率下時的影響，第四、三層熱彈性阻尼分析中探討影響因子分佈在不同的位置下時的表現。
從模擬結果可以得知，由於振盪過程中幾乎沒有厚度方向上的變形，再加上研究中探討為厚短樑與高特徵頻率下，剪應力作用明顯，因此主要是探討等向性平面楊氏模數、等向性平面蒲松比和剪切模數對於位移和熱彈性阻尼造成影響程度分析。

The thermoelastic damping model of Timoshenko microbeam is established, and the influence of transversely isotropic elastic modulus is an important topic. First, the steady-state analysis shows the degree of deformation of Timoshenko cantilever beam, and Young's modulus and Poisson ratio in the thickness direction have little influence. Therefore, thermoelastic damping is only related to the other elastic modulus. The double-layer thermoelastic damping analysis discusses the influence of the volume fraction of transversely isotropic elastic modulus. Lastly, the triple-layer thermoelastic damping analysis shows the influence of the elastic modulus in different positions.
In the study, Young’s modulus and Poisson ratio of the isotropic plane and shear modulus are analysized under displacement and thermoelastic damping. The effect of shear stress is only significant on Timoshenko beam and high eigenfrequencies.

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