磁流變液為一種新穎的智能流體，此材料具有隨外加場強改變本身材料特性改變的現象，利用此可變特性能在工業界上有許多的應用，根據不同之磁流變液工作模式也將對應至不同的應用範疇，本研究主要探討擠壓模式下磁流變液之材料基礎特性，待釐清其特性後進一步作為工程應用設計之參考指標。
本研究透過磁路分析軟體輔助下自行設計製作壓縮試驗平台，以符合磁流變液在擠壓模式下的實驗需求，滿足了等壓條件、擠壓模式下的磁場分布與受力情況和能改變外加場強之功能；設計電磁鐵以電流作為外加磁場調控的參數，根據磁路分析模擬結果設計出磁流變液於擠壓模式下四種不同磁通量分布情形，為有效驗證模擬的準確性，使用高斯計量測電磁鐵表面場強進行與模擬結果的比對，除了在低電流線圈通入0.1安培下誤差較大外，其餘磁場量測結果和有限元素軟體模擬結果差異皆在5%以內，成功驗證模擬結果的可靠性。
透過壓縮實驗得出不同間距下剛性皆隨壓縮量上升而增加的趨勢，整體上可視為漸進式彈簧(progressive rate springs)的特性；藉由通不同電流的實驗得出各實驗參數下實際剛性改變之情形。剛性隨電流增加而非線性上升；在通入高電流和低電流的實驗結果中，可以分離出兩者適用不同之理論模型，高電流下，可以將1.5安培下不同間距之結果近似成2次多項式，藉由斜率之計算即可得出剛性結果。

The magnetic-rheological fluid (MRF) is an intelligent material, and it can change its material properties with changing the external magnetic field. Because of its tunable and reversible properties, it has widely applied in the mechanical industry. There are three common operational modes of MRF which are valve mode, shear mode and squeeze mode. According to its direction of the external magnetic field and the displacement of MRF, we can easily distinguish the mode in which MRF is. When the MRF is in the squeeze mode, it has high energy harvesting and good vibration suppression.
The purpose of this study is focus on understanding material properties of MRF in the squeeze mode and create the references for engineering application design. We design the compression test apparatus by using the finite element method (FEM), and it can make MRF in the homogeneous magnetic field and also help us easily figure out the effects of the external field. Moreover, we also design the electromagnet to control magnetic field by changing the current. This helps us conduct the compression test with different currents. To verify the simulation accuracy, we use a gauss meter to measure the magnetic field on the surface of the electromagnet and compare it with simulation results. The comparing results show that the differences are all within 5 % except the current is 0.1 A.
In the results, the stiffness of MRF increases with increasing compression displacement under different gap size of MRF region and this results can be considered as the properties of progressive rate springs. On the other hand, the stiffness increase with increasing the input current and it is nonlinear. Finally, the results also reveal that the behavior of force-displacement curves are different in low input current and high input current, so the curves should be adapted to the different theoretical models.

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