含奈米碳管之奈米複合材料應變感測器的製備與應用

Fabrication and Application of Strain Sensor Made of Nanocomposites with Carbon Nanotubes

宋棋舜(Chi-Shun Song)

指導教授 ： 葉孟考 ； 戴念華

國立清華大學/工學院/動力機械工程學系/碩士(2010年)

摘要

應變規為工業界重要的量測工具，對於機械、土木、航太、或是醫學的領域提供便利的應變量測。本文中將奈米碳管添加入環氧樹脂或紙漿中以提升基材之導電性質，製成之複合材料可做為應變量測之工具以取代傳統之應變規。奈米碳管具有質輕、高剛性、高強度及優越的電學性質，將其添加入高分子聚合物作為補強材為常見的應用方式。本文中採用的基材為工業界常用的環氧樹脂，及日常生活中常見的紙張。
奈米碳管添加入絕緣性材料時，電流可藉由碳管與碳管的連接而導通，使複合材料的電阻值下降。由碳管連接產生的導電能力隨著碳管間連結的改變而變化，當複合材料的結構變形時，碳管間的間隙增加，試片的體積電阻值隨之提升。本研究藉由偵測材料電阻值的變化，建立應變感測器以取代傳統之應變規。本文中除了量測不同碳管含量之複合材料的機電性質，並量測拉伸應變與複材體積電阻的關係，實驗結果發現在一定應變範圍內拉伸應變與體積電阻值變化呈線性相關。本研究同時探討不同尺寸、溫度、濕度時感測器的變化並以場發射掃描式電子顯微鏡觀察奈米碳管與基材間接合的情形以及碳管在基材中的分散性。最後使用有限單元軟體ANSYS探討感測器的尺寸對量測時產生的影響。

關鍵字

奈米碳管 ； 應變感測器 ； 環氧樹脂 ； 導電性

並列摘要

Strain gauge is an important measurement tool for the industrial sector, especially for mechanical, civil, aerospace, or medical field to facilitate strain measurement. In this paper, the carbon nanotubes added to the epoxy resin or pulp to improve the conducting properties of the substrate. The composite materials can be used as strain measurement instrument to replace the traditional strain gauge. Carbon nanotubes have light weight, high rigidity, high strength and excellent electrical properties, added to polymers as a reinforcing material for the common application form. In this paper, the substrate is the epoxy resin which is commonly used in industry, and paper used in the daily life.
Resistance of the composites decreased and current can be conducted by the connection of carbon nanotubes, when carbon nanotubes added to the insulation material. The conductivity changed by connection of Carbon nanotubes. When the structure deform, the gap between carbon nanotubes increase, then the resistance of the of composite materials increase. In this study, deformation was detected by measure resistance to replace the traditional strain gauge.
In this paper, the conductivity, mechanical properties of composites, and the relationship of resistance and strain was measured. This study also explores the effect of various dimensions, temperature and humidity to the sensor. Observe the matrix and connection of CNT and matrix by field emission scanning electron microscopy to compare with the experimental results. Finally, use the ANSYS to discuss the size effect of the sensor when measuring.

並列關鍵字

Carbon nanotube ； Strain sensor ； epoxy ； conductivity

參考文獻

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