| Mg-based metallic glasses are regarded as a new family of promising materials with high specific strength and excellent corrosion resistance. It makes sense to develop new Mg-based metallic glasses with strong glass forming ability (GFA) especially under the condition of normal equipment (no vacuum) and adopting commercial raw material. Furthermore, the most important factors are preparation method and alloy component in the factors that affect GFA. A lot of research was taken to the preparation technology and GFA of Mg-based metallic glasses based on the two factors.Considering the big viscosity, poor flowability and filling ability of the alloy melt, some preparation methods were developed in this research such as shaking copper mold casting method, smelting master alloy in medium-frequency vacuum induction furnace-- remelting and casting method, powder pressure forming--melting and casting method and copper mold drawing casting method under suction pressure. Compared with each other by experiments, copper mold drawing casting method is the most successful. This method, which adopts the processing of melting in high purity argon shield and drawing-casting under suction pressure in air, has characteristics of easy operation, simple processing and controlling. At the same time, Mg65Cu25Y10 metallic glass was made in experiment for comparison to determine the appropriate processing parameter of new component Mg65Cu25Y10-xNdx(x=0,2,4,6,8,10). The newly developed process is as following: the crucible with raw material is brought into electric resistant furnace at 600℃,then holding for 25 minutes after reached 750℃, subsequently the melts is stirred at 800℃and castes at about 750℃.The preparation processing parameters could be adjusted in small scale according to the varying of alloy compositions.A series of samples with diameter 3 mm were made by copper mold drawing-casting method with commercial raw material. The results show that the alloys with compositions of x=0,4,6 are amorphous and the alloys with compositions of x=2,8,10 are typical crystallines, with some non-crystal microstructure among them.The samples were observed and analyzed by means of optical microscope (OM), differential scanning calorimetry (DSC), scan electron microscopy (SEM), energy spectrometer (EDX) and X-ray diffractometry (XRD). And the influence of Nd element on the GFA of Mg-Cu-Y-Nd multicomponent alloy systems was studied for the first time. The results of SEM and XRD analyzing show that: (Cu, Y) amorphous oxide, which reaches 0.15% in x=0 component alloy and 0.18% in x=4 component alloy at volume content, adequately distributes at the size of 2μm. However, the oxide with so high content didn't affect the GFA of the alloys obviously. Compared with the alloy of x=0,the GFA of the alloy is improved obviously by appropriate addition of Nd. The best GFA with the Tr g 0.592 and ?T x 66K appears at x=4. Furthermore, the result of DSC analysis shows that there is a single melting peak and the (T l ? Tm) is a narrow range of 16K at x=4 and it could be included that x =4 is at or near one of the eutectic points in the phase diagram of Mg-Cu-Y-Nd. The GFA of the alloy of x=6 is improved at a certain extent compared to x=0 and the critical cooling rate of glass forming of the alloy at x=4,6 is 100K/s by estimation. But when x=2,8,10 the component of the alloys deviates from the eutectic points and the results is a wide rang of (T l ? Tm) (104K, 92K, 143K respectively). Therefore the nucleation and growth of crystals are promoted has good chance and lead to crystalline. The main crystal phases in x=2,8,10 alloys are Mg24Y5, Cu5Y, Cu4Nd, Cu2Nd, Mg2Cu, and so on.
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