Zr对Co基合金铸态组织和玻璃形成能力的影响

Influence of zirconium on microstructure and glass forming ability of Co-based alloy

采用单辊旋淬法制备Co-Fe-Zr-Nb-B多元合金非晶薄带。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)和差示扫描量热仪(DSC)对样品的微观组织、物相组成及热稳定性进行检测分析,以研究Zr元素含量对其铸态组织和玻璃形成能力的影响。结果表明:在合金中适量添加Zr元素有利于提高铸态组织的细小均匀化程度,同时,合金具有较强玻璃形成能力和较高热稳定性。Zr元素含量为4%(原子分数)时铸态组织最均匀细小,具有很好的非晶形成能力及热稳定性,其玻璃转变温度Tg,初始晶化温度Tx和过冷液相区(SLR)宽度ΔTx或(Tx?Tg)分别为870.32、936.28和65.96 K。

Cobalt-base amorphous alloy ribbons were prepared by means of melt-spinning. The influences of zirconium content on the microstructure of as-casting alloy and glass forming ability were investigated by scanning electron microscope （SEM）, X-ray diffraction analyses （XRD）, differential scanning calorimetry （DSC）. The results show that a small amount addition of zirconium is beneficial for improving microstructure of master alloy. Meanwhile, the strong glass forming ability and high thermal stability are attained with 4%（atomic fraction） zirconium addition. The glass transition temperature Tg, crystallization onset temperature Tx and supercooled liquid region △Tx were 870.32 K, 936.28 K and 65.96 K respectively.