本文選題：電熱驅動器 + 材料溫度相關性��； 參考：《中國地質大學(北京)》2017年碩士論文

【摘要】：基于微機電系統(tǒng)(MEMS)的電熱驅動器可以產生數(shù)十毫牛的力和很小微米的位移。電熱驅動器具有多對V型梁和一個中央板子,在V型梁兩端施加電勢差,V型梁會有電流通過,由電流產生焦耳熱量,熱量使電熱驅動器溫度升高以及誘導熱膨脹,使中央板子產生向前的驅動位移和拉力。研究電熱驅動器的熱-力耦合模型以及熱-位移耦合模型。電熱驅動器的制作材料采用多晶硅,多晶硅的材料特性是溫度相關的,在電熱驅動器熱-力耦合模型、熱-位移耦合模型中考慮到了溫度相關的材料特性。電熱驅動器V型梁結構的力學反應,通過V型梁結構的一半單一斜梁能夠同等地計算出來。建立關于電熱驅動器關鍵單元斜梁的三種理論模型:簡支梁模型、定向鉸支座模型、固定端模型。溫度相關材料性對斜梁臨界支反力、軸向內力,以及溫度相關材料特性對斜梁隨溫度升高產生位移是本質重要的。溫度相關材料特性對電熱驅動器最大允許施加電勢差、溫度分布云圖、位移分布云圖是極為重要的。隨著納米科技的發(fā)展,當斜梁的尺寸變成納米級別時,尺寸效應對于楊氏模量、熱膨脹系數(shù)的影響變得重要起來。尺寸效應對于納米斜梁力學表現(xiàn),如臨界支反力、溫度升高產生的支反力是極為重要的。
[Abstract]:Electrothermal actuators based on MEMS (MEMS) can produce tens of millibull force and very small micron displacement. The electric heat driver has many pairs of V-shaped beams and a central plate. When the potential difference between the two ends of the V-shaped beam is applied, the V-shaped beam will have an electric current passing through, resulting in joule heat produced by the current, and the heat will increase the temperature of the electrothermal actuator and induce thermal expansion. Causes the central plate to produce the forward drive displacement and the pull force. The thermal-mechanical coupling model and thermal-displacement coupling model of electrothermal actuator are studied. The material of electrothermal actuator is made of polycrystalline silicon, and the material characteristic of polysilicon is temperature-dependent. The thermal-mechanical coupling model and thermal-displacement coupling model of electrothermal actuator are used to consider the temperature-dependent material characteristics. The mechanical response of V-beam structure with electrothermal actuator can be calculated equally by half of the single skew beam of V-beam structure. Three kinds of theoretical models of oblique beam with key elements of electrothermal actuator are established: simply supported beam model, directional hinge support model and fixed end model. The critical supporting reaction force axial internal force and temperature-related material properties of temperature dependent material are essential to the displacement of oblique beam with the increase of temperature. The properties of temperature-dependent materials are of great importance to the maximum allowable potential difference, temperature distribution, and displacement distribution of the electrothermal actuator. With the development of nanotechnology, the effect of size effect on Young's modulus and coefficient of thermal expansion becomes important when the size of oblique beam changes to nanometer level. The size effect is very important for the mechanical behavior of nanometer skew beam, such as the critical branch reaction force and the branch reaction force caused by the increase of temperature.
【學位授予單位】：中國地質大學(北京)
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TH-39
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本文編號：1878267