Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/2031
標題: 接觸時間與負荷率對表面摩擦與滯滑運動之影響
On Stick-Slip and Surface Friction Under the Effects of Contact Time and Loading Rate
作者: 高聰賢
關鍵字: 負荷率;滯滑運動
出版社: 機械工程研究所
摘要: 
當兩接觸表面以低速作相對運動時,因摩擦力的作用,會發生斷
續移動的現象,稱為滯滑運動。本文首先量測兩相對接觸面間乾摩擦
或界面潤滑的情況下,施加不同的切線負荷率,藉以得到靜摩擦係數
與停滯時間之函數關係,再將所得的函數代入理論解析,以數值方法
說明滯滑運動現象。本文的實驗結果顯示,滯滑運動裡之靜摩擦係數與
停滯時間之函數關係圖形及靜摩擦係數與切線負荷率的關係圖分別呈
S及倒S型,在停滯時間較長或較短及切線負荷率較小或較大的時候,分
別趨於定值,在兩者之間則有漸進的變化,和過去的研究者的圖形相
吻合,動摩擦係數與滑動速度之間則呈指數型的摩擦模式。接觸表面
壓力則與靜摩擦係數在一定範圍內有反比的關係存在,另外,μs-ts
圖的變化區間控制著滯滑運動振動趨於穩定週期,最大靜摩擦係數恆
定值的區間振動穩定,變化較大的區域則需數個振動週期後才能趨於
穩定。對於滯滑運動頻率的觀察,本文的實驗及數值結果均顯示增加
滯滑運動的驅動速度,其頻率就隨著增加而逐漸趨近於自然頻率。

When two contact surfaces move in a relatively low velocity, there occurs a discontinuous movement, known as stick-slip motion, due to the presence of friction force. An experimental apparatus is constructed to measure the functional relation of static friction coefficient and stick time under different tangential loading rate while two contact surfaces are in dry or boundary lubricated conditions. The function thus obtained is used in theoretical analysis to describe stick-slip phenomenon. the experimental resultsshow that the diagrams of μ-ts and μs-F relations are S type and reverse S type, respectively. It means that static friction coefficient approaches constant value as stick time or tangential loading rate tends to larger or smaller value. Among these two bounds is an area that μs varies moderately. These experimental results are confirmed by other investigator's research. The model of the dynamic friction coefficient verse speed reveals as a function of exponential type in the present sliding pairs. It's also found that the static friction coefficient is inversely proportional to the surface contact pressure. Stick-slip motion oscillates stably int he region of constant maximum static friction while several abnormal oscillations are found before stick-slip motion goes to steady state for the case where μs locates in the varying region. Moreover, both the experimental and numerical results show that the frequency of stick-slip motion increases with driving speed and approaches the natural frequency of the system.
URI: http://hdl.handle.net/11455/2031
Appears in Collections:機械工程學系所

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