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Surface morphologies of Zr52.5 Al10 Ni10 Cu15 Be12.5 bulk metallic glass after being rolled at both a temperature around T9 and near ( Tx - 50) K were investigated with a scanning electron microscopy. Macroscopic and microscopic observation results show that squamae, cracks, steps and wedges exist on the surface when the samples were rolled at temperatures around Ty. However, a smooth and fiat surface appears when the samples were rolled at temperatures near ( Tx - 50) K. These results indicate that the mode of deformation in the supercooled liquid region is a partially homogeneous flow at a temperature around T9, and a fully homogeneous one at temperatures near ( Tx - 50) K. According to the results, it is more feasible to roll the amorphous alloys at temperatures near ( Tx - 50) K to obtain parts with smooth and fiat surface. 相似文献
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孙龙 《实验室研究与探索》2005,24(8):19-20
介绍了用于压力测量的新型bridgman装置,并结合X射线衍射分析技术(XRD)研究了常压、高压条件下Zr41.2Ti13.8Cu12.5Ni10Be22.5块体非晶合金的晶化。结果表明,在相同的退火条件下(400℃,退火3小时),增大压力有利于Zr41.2Ti13.8Cu12.5Ni10Be22.5块体非晶合金的晶化;压力越大获得晶化相的晶粒尺寸越大。 相似文献
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LI Jun TIAN Rui XIAO Xue-shan School of Materials Science Engineering Shanghai University Shanghai P.R.China 《上海大学学报(英文版)》2007,(5)
The hot hardness behavior of Zr_(52.5)Al_(10)Ni_(10)Cu_(15)Be_(12.5) bulk metallic glass is studied from ambient temperature to the temperature over T_x (the onset crystallization temperature) using a hot macro-hardness tester and scanning electron microscopy (SEM).The results show that the hot hardness behavior of Zr_(52.5)Al_(10)Ni_(10)Cu_(15)Be_(12.5) bulk metallic glass can be classified into 4 zones:the glassy zone in which the hardness almost linearly decreases with the increase of temperature,the viscoelastic zone in which the hardness is nearly unchanged,the viscous flow zone in which the hardness quickly tends towards near zero with temperature,and the crystallization zone in which the hardness sharply increases.The high temperature deformation behavior and the easy processable deformation region for bulk metallic glasses are also discussed on the basis of the hot marco-hardness. 相似文献
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采用分离式Hopkinson压杆装置(SHPB)和扫描电镜(SEM)技术研究了不同高应变率下Zr基非晶合金样品(Zr55Cu30Al10Ni5)的变形行为和断口形貌。研究发现与准静态压缩形变相比,高应变率水平(3400 s-1和1900 s-1)下,非晶合金样品断裂应力显著降低,最大降低约达40%。扫描电镜形貌观察表明,非晶合金的高速断裂发生在一条主剪切带上,主剪切面偏离45°最大切应力面。同时断口形貌为明显的脉络花样,并覆盖有大量液滴状和不规则形状熔融物,表明高应变率下断裂表面温升较准晶态断裂有所增加。 相似文献
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1IntroductionSince a non-noble bulk metallic glassy alloy was dis-covered byInoue ,et al.[1]in 1988 , many stable amor-phous alloy systems with higher glass-forming abilityand lower critical cooling rates have been developed .Among them, Zr-based metallic glassy alloys are in-tenselyinvestigated because of their wider supercooledliquid region and other favorable thermodynamic andmechanical properties .In general ,surface morphologyof amorphous alloy parts is veryi mportant forindustri-al and … 相似文献