直接擠壓鑄造A356鋁合金

Direct Squeeze Cast A356 Aluminum alloy

蔡維翔(Wei-Xiang Tsai)

指導教授 ： 施登士

國立中央大學/工學院/機械工程學系/碩士(2007年)

摘要

本研究在不同製程參數（澆鑄溫度、擠壓壓力）下，利用直接擠壓鑄造方式獲得Al - ( 6.0~8.0 wt.% ) Si - ( 0.3-0.5 wt.%)Mg鋁合金鑄件，用以探討合金成分、介在物/微孔數目和氧化膜對於洛氏硬度和拉伸性質的影響。
實驗結果顯示：（1）合金成分中矽和鎂元素含量增加可提高鑄件平均硬度和機械性質，但氧化膜和介在物會增加；（2）鑄件內殘留的介在物數目遠少於共晶矽，因此對於洛氏硬度影響不明顯；（3）微孔對於硬度影響取決與微孔尺寸與數目；（4）鑄件內殘留的氧化膜對於鑄件硬度分佈無明顯的關連；（5）Al-6.0Si-0.3Mg鋁合金在擠壓壓力120MPa，澆溫685℃和模溫180-200℃的製程參數下可獲得最佳的拉伸試驗可靠度（Weibull parameter：53.7）；Al-7.64Si-0.52Mg鋁合金在擠壓壓力60MPa，澆溫685℃和模溫180-200℃的製程參數下會獲得最差的拉伸試驗可靠度（Weibull parameter：9.9）。

關鍵字

A356鋁合金 ； 擠壓鑄造 ； 氧化膜 ； 微孔 ； 介在物

並列摘要

Effects of particle/pore counts, oxide film, and alloy compositions on hardness and mechanical properties of squeezed cast Al-7Si-0.4Mg alloys at different process parameters ( pouring temperature and squeeze pressure ) were investigated in this study.
Experimental results show that: (1) Increase both magnesium and silicon content slightly increase hardness and mechanical properties of squeezed Al-7Si-0.4Mg alloy. (2) Particle counts trapped in squeezed Al-7Si-0.4Mg show low fraction of eutectic silicon. (3) Pore counts effects the measured hardness of squeezed Al-7Si-0.4Mg alloy. (4) Reliability on UTS is highest (Weibull parameter for squeezed Al-6Si-0.3Mg alloy is 53.7) when pouring temperature is 685℃, mold temperature remains 180-200℃ and squeeze pressure keeps 120MPa.

並列關鍵字

pore ； oxide film ； squeeze cast ； A356 aluminum alloy ； particle

參考文獻

1. S. Rajagopal & W.H. Altergott, “Quality Control in Squeeze Casting of Aluminum”, AFS Transactions, 92(1982), .539-546

3. S. Okada, N. Fujii, A. Goto, S. Moroimoto & T. Yasuda, “Development of a Fully Automatic Squeeze Casting Machine”, AFS Trans. 90(1982), 135-146

4. Shunsaku Komatsu and Yoshinobu Kanoh, “Development and MassProduction of Squeeze Casting Technique”, 鑄物, 64（1992）

8. J.H. Lee , H.S. Kim , C.W. Won, B. Cantor, “Effect of the gap distance on the cooling behavior and the microstructure of indirect squeeze cast and gravity die cast 5083 wrought Al alloy”, Materials Science and Engineering A, 338 (2002) , 182-/190

10. S, Hama, F. Watanabe, N. Minami & A. Yoshizawa, “Development of Atmospheric Pressure Controlled Aluminum Casting Process”, Light Metal, 44, n.12, 727-732