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In this paper, prepared by copper mold casting the wedge amorphous alloy samples to show differential scanning calorimetry instrument ( DSC ) , scanning electron microscopy ( SEM ) , X - ray diffraction as the main means , respectively as larger atoms Al , Ag Zr -Cu binary alloy crystallization process interference and the law , and as a small atom of Fe on the Zr-Cu-Al and Zr-Cu-Ag ternary amorphous forming ability . The analysis results showed that as the third element having a larger atomic radius of Al, Ag , Zr-Cu eutectic crystallization process there was a strong interference effect . Specific performance: 1) test Zr-Cu-Al and Zr-Cu-Ag ternary alloy with a strong glass-forming ability . 2) In the crystal structure of the wedge-shaped sample of Zr-Cu-Al, Zr -Cu - Ag alloy , Al , an Ag elements Zr-Cu precipitated in the leading phase of the concentration is low, around the leading phase has higher concentration of Al , Ag elements through in leading phase precipitated during the concentration of the solute redistribution phenomenon occurs , thereby Zr-Cu intermetallic phase formation plays a hindered , so that the other hand, improve the amorphous formation capacity. Fe, having a smaller atomic radius as the fourth element of the ternary alloy of Zr-Cu-Al and Zr-Cu-Ag , a difference of more than 12% of the conditions found with other atomic radius , but the added result is played a role in promoting the crystallization process of the two alloy systems , thereby undermining the glass-forming ability . Specific performance: 1 ) for Zr-Cu-Ag alloy adding Fe Fe atomic radius smaller , easy to spread, so reduced Ag precipitation of Zr-Cu phase hindered , thereby promoting ZrCu phase formation , and thus cause the entire system crystallization process in advance , the destruction of the glass-forming ability ; 2) for Zr-Cu-Al alloys , Fe added greatly reduce the size of the wedge-shaped sample of amorphous regions . SEM analysis showed that the Zr-Cu-Al-Fe alloy containing Fe 5% before crystallization occurs the phenomenon of phase separation , so that phase separation results is formed in the supercooled liquid rich in Fe , Al zone and the Cu-rich zone , in the subsequent cooling process , the two regions are crystallized , thereby accelerating the whole crystallization process . This greatly worsened the glass-forming ability .
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