形狀記憶合金之彈性係數的溫度效應之研究

A STUDY ON TEMPERATURE EFFECT OF ELASTICITY OF SHAPE MEMORY ALLOY

林振寧(Chen-Ning Lin)

指導教授 ： 葉隆吉

大同大學/工程學院/機械工程學系所/碩士(2005年)

摘要

摘要
形狀記憶合金的記憶效應，乃藉由溫度的升降，所引起的相變化所驅動，且由先前的研究發現，懸臂式的SMA在不同電流的加熱下，呈現出不同的剛性，會有不同的負荷能力，所以本研究假設-SMA的剛性為其自身溫度的函數，以懸臂式的SMA實驗，通以不同的電流，於SMA擬彈性效應狀態下,測其荷重與變形量間的關係，再將結果代入ANSYS所建模型中分析，估算其等效的彈性係數(E)，並以所通的電流(A)，透過牛頓冷卻定律(Newton’s low of cooling)，推算出SMA的溫度(Ts) ，如此藉由一系列的實驗資料及分析結果，迴歸分析出彈性係數E隨溫度而變化的函數關係。
研究結果發現，本研究假設SMA在100%沃斯田體與100%麻田散體相變化範圍內，其彈性係數會受到自身溫度，亦即相對於其所流通之電流值，與其出力大小的影響。最後，在兩個相變化範圍內，發現線徑為0.6mm的SMA線，輸入電流2~3安培時，懸臂出力為0.6~0.8牛頓的條件下，可建立其彈性係數與溫度的理論關係式。

關鍵字

形狀記憶合金

並列摘要

Abstract
The memory effect of the shape memory alloy is driven by phase transition caused by the rise or fall of temperature. In addition, it is discovered from the previous research that under heating of the cantilever SMA with different currents, different rigidity will be revealed and there will be different loading capability. Therefore, this research assumes that the rigidity of SMA is the function of its own temperature. Then based on the cantilever SMA experiment, different currents are passed through and the correlation between its loading and deformation value is tested under the pseudoelasticity condition of SMA. Thereafter the result is being substituted into the model constructed by ANSYS to conduct analysis in order to estimate its equivalent coefficient of elasticity(E). In addition, based on the current(A) that passed through, the temperature of SMA (Ts) is calculated based on Newton’s law of cooling. In this way, through a series of experiments data and analysis result and regression analysis, the function correlation of the coefficient of elasticity E that follows the change of temperature can be obtained.
The research result discovers that this research assumes that the SMA is within the 100% Austensite and 100% Martensite phase transition range. Its coefficient of elasticity will be affected by its self-temperature that means corresponding to its circulating current value and its force. Finally, within the two phase transition ranges, it is discovered that when the wire diameter is 0.6 mm SMA and the input current is 2~3 ampere and the cantilever force is under the 0.6~0.8 Newton’s condition, the theoretical correlation formulae of its coefficient of elasticity and temperature can be established.

並列關鍵字

SMA

參考文獻

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