熱處理對7050含鈧鋁合金顯微結構及機械性質之影響

The Effects of Heat Treatment on the Microstructure and Mechanical Properties of 7050 Aluminum Alloys Containing Scandium

彭煥之(Huan-Chih Peng)

指導教授 ： 邱傳聖

元智大學/工程學院/機械工程學系/碩士(2008年)

摘要

7000系列鋁合金其特色為具有優異的析出強化，當添加稀土元素鈧後其機械性質會隨之變化。故本研究針對7050含鈧鋁合金在不同熱處理條件下，探討其顯微組織及機械性質之變化。

本研究分二部分探討，第一部分為探討時效處理對7050含鈧鋁合金之顯微組織變化。第二部分為探討7050含鈧鋁合金經時效處理對其機械性質之影響。

實驗結果顯示，當進行二階段時效處理120℃時效6小時加150℃時效6小時，此合金有最佳機械性質，其硬度、強度與伸長率可達硬度值達Hv285、抗拉強度達666MPa及伸長率達6%。在顯微結構方面，基底則是產生均勻且細密之析出物。

關鍵字

含鈧鋁合金 ； 時效處理 ； 析出強化

並列摘要

7000 series aluminum alloys has excellent properties in precipitation hardening. When scandium added that could modify mechanical properties. This study was to investigate the influence of precipitation hardening effect and the mechanical properties on aging treatment during the different heat treatment of 7050 aluminum alloys containing scandium.

This study was divided into two parts. First parts of this study investigated the precipitation hardening effect on 7050 aluminum alloys containing scandium during aging treatment. Second part of this study discussed the mechanical properties of this alloy on aging treatment.

It is proposed that the optimal aging treatment parameters were aging at 150℃ for 6h followed with 120℃ for 6 h. The microhardness was Hv285 and the ultimate tensile strength and elongation were 666MPa and 6%, respectively. The microstructure of this alloy after aging possessed uniform and fine precipitate in the matrix.

並列關鍵字

aluminum alloy containing scandium ； age treatment ； Precipitation

參考文獻

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