銅基塊狀非晶合金之研究與開發

The Study of Cu-based Bulk Amorphous Alloys

楊瑜民(Yu-Min Yang)

指導教授 ： 金重勳

國立清華大學/工學院/材料科學工程學系/碩士(2007年)

https://doi.org/10.6843/NTHU.2007.00287

摘要

本研究的目的為探討及發展二元、三元銅基塊狀非晶合金(BMG)，主要分為Cu-Hf-Al、Cu-Y-(M)、Cu-Ti-M (M為合金添加的第三元素)等三個合金系統做討論。
首先為提升既有Cu-Hf BMG的非晶形成能力。將2 at.% Al元素以全取代的方式添加於高Cu含量之Cu65Hf35 (2 mm) 二元非晶合金，可提升非晶形成能力至直徑約3 mm，合金微結構為不均質非晶相。接著嘗試Cu-Y二元合金，得到非晶與結晶共存的結構，最佳成分為Cu78Y22。進行第三元素的全取代，結果以(Cu78Y22)97Ag3合金有最趨於全非晶1 mm棒材的結果。最後嘗試以Cu-Ti為主的三元合金，最佳結果為Cu50Ti40Zr10合金，非晶棒材可達直徑約1 mm。
Cu-Y-M三元合金因微結構為非晶與結晶共存，因此為一脆性材料，且耐蝕性質不佳。全非晶Cu-Hf-Al合金系統表現出最佳的機械性質，壓縮破斷強度可達2340 MPa，且1 mm合金有約1 %的塑性變形量。Cu50Ti40Zr10合金於1 N H2SO4 + 0.01 N NaCl溶液中整體腐蝕電流密度值小於10-5 A/cm2，表現出不錯的電化學性質，此合金並同時擁有高達2000 MPa之壓縮破斷強度。

關鍵字

銅基塊狀非晶合金 ； 非晶形成能力 ； 銅模噴鑄

並列摘要

The purpose of this study was to explore binary and ternary Cu-based bulk metallic glasses (BMG), which were divided into three systems: Cu-Hf-Al, Cu-Y-(M), Cu-Ti-M alloys, where M is an additive element.
First, high Cu-content binary Cu-Hf BMG modified with Al, (Cu65Hf35)100-xAlx (x= 1, 2, 3, 4, 6) were studied. With only x= 2, the glass-forming ability (GFA) is greatly improved to form bulk glassy rod up to at least 3 mm in diameter. The microstructure consists of inhomogeneous amorphous phases. The Cu-Y binary system was chosen to study the GFA on compositions around the eutectic points and their modification. The microstructure of as-cast Cu-Y rods contained amorphous and crystalline mixture phases. According to the XRD results the best glass forming alloy is Cu78Y22. The further addition of Ag improves the GFA. The composition (Cu78Y22)97Ag3 was very close to form fully 1 mm BMG rod. Finally, we tried to develop the ternary BMGs based on high Cu content Cu-Ti BMG. The best result is the Cu50Ti40Zr10 glassy rod with the diameter at least 1 mm.
The Cu-Y-M ternary alloys are brittle and poor electrochemical resistance due to their structure that contained amorphous and crystalline phases. Fully amorphous Cu-Hf-Al system showed the best mechanical properties with a compressive fracture strength up to 2340 MPa and a plastic strain up to about 1 % due to the inhomogeneous amorphous phases. Cu50Ti40Zr10 alloy performed low corrosion current density, 10-5 A/cm2, in 1 N H2SO4 + 0.01 N NaCl solution showed excellent electrochemical property, and its compressive fracture strength is up to about 2000 MPa.

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