(合肥工业大学 材料科学与工程学院 金属液/固加工研究所，合肥 230009)
摘 要: 以Zr48Cu36Al8Ag8为研究对象，结合差示扫描量热法和X射线衍射法，以电阻法探索高流变成型法对块体非晶合金β弛豫及热稳定性的作用规律。升温速率为10 K/min的验证试验表明，电阻法所标定样品的β弛豫开始温度Tβ、一次晶化开始温度Tx-onset及其区间等特征参数均与差示扫描量热法结果相吻合。这证明电阻法探索β弛豫及热稳定性的有效性。为进一步获得更细致信息，以升温速率1 K/min约化电阻率曲线揭示，高流变成型法成型后样品的Tβ大幅提前，且β弛豫所致电阻率变化值Δρrel显著增加，表明高流变成型法显著增强该块体非晶合金β弛豫强度；成型后Tx-onset滞后且晶化温度区间ΔTx变宽，反映高流变成型法提高了该块体非晶合金的热稳定性。这一结论得到不同温度水淬样品X射线衍射结果证实，尽管成型前后的最终晶化相并未改变。
关键字: 块体非晶合金；高流变成型法；β弛豫；热稳定性
（Liquid/Solid Metal Processing Institute, School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China）
Abstract:This work, combining with differential scanning calorimetry (DSC) and X-ray diffraction (XRD) methods, adopts the resistivity method to investigate the effects of HRRF on β relaxation and thermal stability of Zr48Cu36Al8Ag8 bulk metallic glass (BMG). The verification tests at a heating rate of 10 K/min show that, the characteristic parameters calibrated by the resistivity method, like β relaxation onset temperature Tβ, the first crystallization onset temperature Tx-onset and its related interval, are consistent with DSC results perfectly, which manifests the effectiveness of the resistivity method on exploring β relaxation and thermal stability of Zr48Cu36Al8Ag8 BMG. For more detailed information, the normalized resistivity curves at a heating rate of 1 K/min are obtained, which uncover a sharp Tβ advance and a significant increase in the resistivity change value Δρrel contributed by the β relaxation of the formed BMG, indicating an intensified β relaxation of the formed BMG; furthermore, obviously lagging Tx-onset and broadening ΔTx of the formed BMG evince significantly enhance thermal stability of the formed BMG, which gets further confirmation by XRD results of the water-quenched samples at different temperatures, despite the identical final crystallization phases of both as-cast and formed BMG samples.
Key words: bulk metallic glass; high rheological rate forming method; β relaxation; thermal stability
