真空度对Zr-Al-Cu-Ni合金大块玻璃形成的影响

在两种不同的真空度下,运用真空电弧炉熔炼合金制备试样;运用X射线衍射技术和晶相显微技术对试样进行了分析和讨论.结果表明:用真空电弧炉熔炼合金能得到比较均匀的母合金熔体;由于Zr-Al-Cu-Ni合金与铜型之间的润湿角很大,因而形成玻璃能力强;高真空度、原材料成分的纯度是Zr-Al-Cu-Ni合金形成玻璃态的重要因素;金属合金熔体随水冷铜型一起冷却,在真空度不高的条件下,由于合金熔体中的组元与空气中的氧、氢及氮反应形成晶核,而合金熔体与铜型之间的温度梯度不大,无法抑制晶核的生长,因而无法获得完全玻璃态.

Influence of Vacuum Degree on Bulk Metallic Glasses' Formation for Zr-Al-Cu-Ni

Bulk amorphous alloys have been favored because of their excellent properties, but the preparation technology is the important things of their application. The samples were prepared by using the vacuum arc furnace on the condition of two kinds of different vacuum degree methods. And the samples were analyzed in X-ray diffraction technology, micro-photograph technology and SEM. The results are obtained, the fairly even alloy can be obtained through the method that the alloy was melted in the arc furnace vacuumed. The wetting angle between the copper mold and Zr-Al-Cu-Ni alloy melt is rather big, so the glass forming ability is strong. High vacuum degree and purity of materials are important factors for forming glasses for Zr-Al-Cu-Ni alloys. Under no high vacuum degree, when the alloy melts are cooled following with the copper mold cooled in water, because the nuclei are formed by reaction between Oxygen, Nitrogen and Hydrogen and components of alloys, and the temperature gradient between copper mold and alloy melts is not big enough that the growth of the nuclei is not able to be checked, the glass state cannot be fully acquired.