超聲處理對2219大規格鋁錠微觀組織與宏觀偏析的影響

鐘貞濤; 李瑞卿; 李曉謙; 陳平虎

doi:10.13374/j.issn2095-9389.2017.09.007

超聲處理對2219大規格鋁錠微觀組織與宏觀偏析的影響

doi: 10.13374/j.issn2095-9389.2017.09.007

鐘貞濤^1,2,
李瑞卿^2,3, ,,
李曉謙^1,2,3,
陳平虎^1,2

1) 中南大學機電工程學院, 長沙 410083
2) 中南大學高性能復雜制造國家重點試驗室, 長沙 410083
3) 中南大學輕合金研究院, 長沙 410083

基金項目:

國家自然科學基金資助項目(51475480,5160496,U1637601)

詳細信息

中圖分類號: TG249.7
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出版歷程
- 收稿日期: 2016-12-10

Effect of ultrasonication on the microstructure and macrosegregation of a large 2219 aluminum ingot

ZHONG Zhen-tao^1,2,
LI Rui-qing^{2,3
, ,},
LI Xiao-qian^1,2,3,
CHEN Ping-hu^1,2

1) School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China
2) State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, China
3) Light Alloy Research Institute, Central South University, Changsha 410083, China

摘要

摘要: 在半連續鑄造過程中施加超聲,成功制備了φ1250 mm 2219鋁合金鑄錠.利用光學顯微鏡、掃描電鏡、能譜儀及直讀光譜儀等儀器對鑄錠的組織與成分分布進行檢測與分析,探究超聲對鑄錠組織與偏析的內在作用機制.研究結果表明:超聲振動引起的空化和聲流效應能明顯均勻組織結構,細化晶粒,尤其是心部晶粒細化率達到39.6%.超聲促進鑄錠晶間第二相呈枝丫狀斷續分布,晶內析出物點狀彌散分布.同時,超聲有效減小近表面負偏析,降低邊部與心部之間的溶質濃度差異,弱化整個橫截面的濃度波動,從而改善宏觀偏析.
- 半連續鑄造 /
- 超聲波 /
- 晶粒細化 /
- 第二相 /
- 宏觀偏析
Abstract: By applying ultrasonication during direct chill casting, a 2219 ingot with a diameter of 1250 mm was successfully produced. To study ultrasonic inner mechanism of ingot, the microstructure and macrosegregation of ingots cast after ultrasonication were analyzed by optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and direct-reading spectrometry. The results show that the cavitation and acoustic streaming effects brought by ultrasonic vibration can obviously regulate the structure and refine the grain size of the resulting ingots. The central grain refinement rate observed is 39.6%. Ultrasonication promotes the formation of branched intergranular secondary phases with a discontinuous distribution, and transgranular precipitates present a dispersed distribution with dot. Ultrasonication also effectively decreases negative segregation near the surface of the ingots, reduces the difference solute concentration between their edge and center, and weakens fluctuations in concentration over the entire cross section of the samples, thereby improving the macrosegregation properties of the final products.
- direct chill casting /
- ultrasonic /
- grain refinement /
- second phase /
- macrosegregation

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參考文獻(7)

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