高強度及高傳導性質的銅合金/奈米碳纖複合材料之研究

Study on High Strength and High Conductivity of Copper Alloy with VGCF Composites

陳冠宇(Kuan-Yu Chen)

指導教授 ： 蔡宏營

國立清華大學/工學院/動力機械工程學系/碩士(2012年)

摘要

本研究使用奈米碳纖與銅合金材料製作複合材料，期望能藉由奈米碳纖(氣相成長碳纖維，VGCF)加強銅合金材料的機械性質。銅鈦合金粉末(鈦含量0.4 mass%)與混合用油、奈米碳纖依序以球磨機、振動研磨機均勻混合。接著以放電電漿燒結機，在溫度1223 K、真空環境下進行燒結，燒結後的圓柱型材料以加熱爐，在氬氣環境、1073 K 的溫度下預熱後擠出。結果上，銅鈦合金材料在未添加奈米碳纖的情況下得到的降伏強度與電傳導率分別為254.7 MPa及46.0 IACS%。而銅鈦/奈米碳纖複合材料的強度略低於銅鈦合金，傳導率卻有近兩倍的提升。與相同製程的純銅材料相比，傳導率僅下降10 IACS%，強度卻提高了約兩倍。本研究同樣將銅矽合金、銅鉻合金材料與奈米碳纖製作複合材料，作為銅鈦/奈米碳纖複合材料的對照，並提出複合材料製作過程中的反應機制，對於材料機械特性的變化進行討論。

關鍵字

奈米碳纖 ； 合金 ； 機械性質 ； 掃描式電子顯微鏡 ； 燒結

並列摘要

Copper alloy reinforce with vapor-grown carbon fiber (VGCF) was fabricated in order to improve mechanical properties of original materials has been reported in this studied. Cu alloy powder with 0.4 mass% Ti was mixed with Clesafe oil facilitate coating of VGCF on alloy powder by ball milling before mixing with VGCF by rocking mill. Spark plasma sintering (SPS) was performed at 1223 K in vacuum and 30 MPa load was applied during SPS. Cylindrical specimens were extruded with preheating temperature at 1073 K. As a result, Cu-Ti alloy specimen without VGCF shows yield stress and electrical conductivity at 254.7 MPa and 46.0 IACS% respectively. It appears that yield strength of Cu-Ti/VGCF composite material is inferior than original alloy but electrical conductivity is improved. Copper-Silicon alloy reinforced with VGCF was also fabricated with same procedure in purposed of comparing with Cu-Ti/VGCF composites. Hardness and electrical conductivity of this material was degraded compared with original alloy.

並列關鍵字

Carbon nano fibres ； Alloys ； Mechanical properties ； Scanning electron microscopy ； sintering

參考文獻

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