(1. 北京航空航天大學(xué) 材料科學(xué)與工程學(xué)院，北京，100191；
2. 北京理工大學(xué) 材料科學(xué)與工程學(xué)院，北京，100081)
摘 要: 利用銅模鑄造法制備Zr50Cu50二元非晶合金，并研究銅模溫度、保護(hù)氣體對Zr50Cu50合金非晶形成的影響。熔液的冷卻速率是由銅模溫度以及保護(hù)氣性質(zhì)共同決定的，相比于氬、氦作為保護(hù)性氣體不但有效提高熔液的冷卻速率，而且在超低溫制備環(huán)境下仍能保持樣品表面光滑。在此研究基礎(chǔ)上，利用氦作為保護(hù)氣，在液氮作為銅模冷卻介質(zhì)的超低溫環(huán)境下(79 K)，制備出表面光滑、直徑為2.5 mm的Zr50Cu50大塊非晶合金，該尺寸超越了之前所報道的Zr50Cu50非晶合金的最大尺寸(2 mm)。
關(guān)鍵字: 非晶合金；模具溫度；保護(hù)氣體；冷卻速度；非晶形成能力
（1. School of Materials Science and Engineering, Beihang University, Beijing 100191, China;
2. School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081, China）
Abstract:The Zr50Cu50 binary bulk metallic glasses were prepared using cooper mold casting. The effects of cooper mold temperature and protective gas on the glass-forming ability were studied. The cooling rate of alloy melt was controlled by cooper mold temperature and protective gas properties. Compared with Ar, He as protective gas speeds up the cooling rate, at the same time, it can improve the smoothness of alloy samples surface under ultra low temperature. The fully amorphous alloy with diameter of 2.5 mm can be cast for Zr50Cu50 by using He as protective gas and liquid nitrogen as cooling medium under ultra low temperature environment (79 K). The size of Zr50Cu50 binary bulk metallic glasses exceeds the maximum dimension of 2 mm.
Key words: metallic glasses; mold temperature; protective gas; cooling rate; glasses forming ability
