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Bulk amorphous crystal and microcrystal for Pr60Cu(20-x)Ni10Al10Fex (x=0, 8, 15, 20) with the diameter of Φ 2~6 mm were manufactured by electric arc smelting, high frequency heating and copper mold upper suction casting, and its structure was analyzed by X-ray diffract meter. It showed soft magnetic characteristic gradually when Fe content in it was up to 8%. The material was applied to magnetic-electric sensor as key component, output signal of which was measured with the change of Fe content. It shows that the signal changes from weak to strong with the increase of Fe content and presents the largest peak value when Fe is replaced by Cu completely. 相似文献
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锆基块体非晶合金具有优良的非晶形成能力,可在很小的冷却速率条件下获得.锆基非晶合金具有高强度、超塑性、高弹性、高硬度、高耐磨性和高耐腐蚀性能等,有着广阔的应用前景.总结了锆基非晶合金的形成机制,着重对锆基非晶合金的力学性能、耐腐性能等进行了综述. 相似文献
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利用射流成型法制备出Zr52.5Cu17.9Ni14.6Al10Ti5大块非晶.该合金系统具有很强的玻璃形成能力和宽的过冷区,其玻璃转化温度Tg=650.63K,晶化温度Tx=721.90K,过冷区△Tx=Tx-Tg=71.27K.Vicker硬度为558kg/mm2压缩断裂强度1730GPa,弹性模量82GPa.观察其断口有大量纹络状河流花样,并有融化的液滴存在.该合金系统大的玻璃形成能力应归功于合金组元的多样性、组元间大的原子半径比率、组元间大的混合负热及在冷却过程中过冷区粘度的急剧上升等因素. 相似文献
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大块锆基非晶合金电化学耐腐蚀行为的试验研究 总被引:1,自引:0,他引:1
利用电化学极化曲线方法研究了Zr41Ti14Cu12.5Ni5Be22.5Fe5非晶合金及成分相同的晶化合金及纯Zr在硫酸溶液中的腐蚀行为。利用减重法研究了Zr41Ti14Cu12.5Ni5Be22.5Fe5非晶合金及成份相同的晶化合金在浓硫酸溶液中的腐蚀行为。极化曲线测试结果表明,非晶合金及成分相同的晶化合金与纯金属Zr有很大差异:非晶合金过钝化电位最高,钝化区最长,而纯金属Zr过钝化电位最低;钝化区也最短。减重试验表明,非晶合金的腐蚀速率是成分相同晶化合金的1/4。以上结果表明非晶合金拥有优良的耐腐蚀性能。 相似文献
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本文选用非晶形成能力高,且在玻璃转变区和过冷液相区有高热稳定性的Cu46Zr47-x Al7块体非晶合金为研究对象,利用差示扫描量热分析(DSC)、高温真空压缩实验等方法,对其高温均匀塑性流变行为进行研究。结果表明,Cu46Zr47Al7块体非晶合金的高温均匀塑性形变行为依赖于温度和应变速率,随着温度的降低或应变速率的增大呈现出牛顿流变向非牛顿流变的转变,该行为可以用基于自由体积的过渡态理论来进行定量描述。根据过渡态理论拟合出来的驱动体积大致相当于25~50个原子,驱动能为551kJ/mol,说明控制合金高温均匀形变的原子不会脱离周围原子而单独跃迁,其扩散涉及到多原子的协同运动。 相似文献
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向以Zr80Co15Al5为基体的非晶合金中添加微量铜和镍,利用铜模吸铸法和半固态处理工艺制备棒状(Zr0.88Cu0.12)95-2x Al5(NiCu)x(x=1.5、2.5、3.5)非晶合金。利用SEM、XRD和光学显微镜(OM)分析研究了半固态处理工艺对非晶合金的微观组织结构、玻璃形成能力及断口形貌的影响。结果表明,在半固态处理工艺基础上对Zr80Co15Al5添加微量铜和镍后有较好的晶体形成能力。 相似文献
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块体金属玻璃的研究现状 总被引:1,自引:0,他引:1
介绍了块体金属玻璃的研究和进展。阐述了常见的制备块体金属玻璃的主要方法,如熔体水淬法、铜模吸铸法、熔体喷铸与真空吸铸相结合的制备技术、压铸法、定向凝固铸造法、磁悬浮熔炼铜模冷却法、以金属玻璃为基复合材料的制备方法以及金属玻璃合金丝和管的制备,简要说明了块体金属玻璃的性能特征及应用,并提出了研究过程中值得重视的三个问题。 相似文献
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采用铜模吸铸法成功制备了Cu50Zr42Al8块状非晶,用纳米压痕法研究了铸态和低于玻璃化转变温度(Tg)退火后试样的力学性能,等温退火后试样的塑性增加而硬度和弹性减小。 相似文献
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Crystalline Behavior and Magnetic Properties of Nd60Fe30-x Al10Cox(x = 0,5,10) Bulk Amorphous Alloys
Crystalline behavior and magnetic properties of Nd60Fe30-xAl10Cox( x = 0, 5, 10) bulk amorphous alloys were investigated by differential scanning calorimeter (DSC), X-ray diffraction (XRD) and the vibrating sample magnetometer (VSM). Neither glass transition nor supercooled liquid region before crystallization was observed for the as-cast Nd60Fe30-xAl10Cox ( x = 0,5,10) bulk amorphous alloys. The glass forming ability can be improved significantly by the addition of Co. The as-cast Nd60Fe30-xAl10Cox (x = 0,5,10) alloys show hard magnetic behavior. With the addition of Co content, intrinsic coercivity (iHc) increases while the saturation magnetization(σs) and remanence (σr) decrease. The Curie temperature for the as-cast Nd60Fe30-xAl10Cox alloys increases from 451 K for x =0 to 468 K for x = 10. Some pre-cipitation of crystalline phases does not affect the hard magnetic properties of Nd60Fe30-xAl10Cox(x = 0,5,10) alloys, while the hard magnetic behavior disappears quickly after the alloys being completely crystallized. 相似文献
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采用单辊旋淬法制备了Cu50Zr42Al8,Cu46 Zr47-xAl7Yx(x=2,5),Cu43Zr42AlsAg7和Cu43Zr42Al8Ag5 Y2非晶合金薄带,利用X射线衍射和差示扫描量热分析研究了合金样品的玻璃形成能力和热稳定性.结果表明,在Cu50Zr42Al8中添加适量的Ag、Y后使得非晶合金的短程有序结构发生改变.合金Cu46Zr47-xAl7Yx(x=2,5)的过冷液相区宽度ΔTx分别比Cu50 Zr42 Al8增加了19K、30K,约化玻璃转变温度Trg从0.565分别增加到0.579和0.566,参数γ从0.402分别增加到0.418和0.420,说明Y的添加提高了非晶合金的热稳定性和玻璃形成能力.合金Cu43Zr42 Al8Ag7和Cu43Zr42Al8Ag5Y2与Cu50Zr42Al8相比,约化玻璃转变温度Trg及参数γ均有了明显的提高,达到了0.619、0.416和0.609、0.411,表明Ag的添加、Ag和Y的同时添加均提高了Cu - Zr -Al系非晶合金的玻璃形成能力,但Ag的效果更加显著. 相似文献
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A method based on the semi-empirical Miedema model and a geometrical model was used to study the glass forming abilities(GFA) and the amorphous forming ranges of Al-Fe-Nd-Zr system and its constituent ternary systems.The amorphous forming composition ranges were analyzed based on different criteria such as ΔGam-ss and PHSS(PHSS=ΔHchem(ΔSC/R)(ΔSσ/R)) for Al-Fe-Nd system.The predicted amorphous forming range was in good agreement with the experimental results.The results showed that the criterion of ΔGam-ss was more accurate,and agreed well with the experiment results.The Gibbs free energy difference ΔGam-ss and parameter PHSS were then used to predict the amorphous forming composition range for the rest of the constitutive ternary systems of Al-Fe-Nd-Zr.In addition,the amorphous forming composition ranges of the(Al-Fe-Zr)100–x Ndx(x=50,60,70) systems were predicted by ΔGam-ss and the modified parameter PHSS.The Gibbs free energy of Al10(Fe1–x Zrx)30Nd60 were also calculated.The GFA parameter PHSS indicated that the composition with the highest GFA was Al33.5Fe13.5Zr3Nd50 for the(Al-Fe-Zr)50Nd50 system,Al28.8Fe10Zr1.2Nd60for the(Al-Fe-Zr)40Nd60 system and Al22.8Fe6.9Zr0.3Nd70 for the(Al-Fe-Zr)30Nd70 system,and the results suggested that those alloys with high content of Al had higher GFA.The appropriate content of neodymium and zirconium resulted in the lower value of PHSS and increased the GFA obviously. 相似文献
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文章利用一种新颖的浓缩沉淀结合后续热处理的方法制备成功微米级氧化铜块状晶体粉末。采用热重分析(TGA)、差式量热扫描(DSC)、X射线衍射(XRD)、扫描电镜(SEM)等分析手段对所获得的前驱体以及煅烧后的粉末进行了表征。结果表明,经过浓缩法制备的前驱体为一种碱式硝酸铜(Cu4(NO3)2(OH)6)粉末,这种前驱体粉末在235℃左右分解成氧化铜(CuO),CuO粉末的平均粒径约为5μm且为一种块状晶体粉末。 相似文献
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《钢铁研究学报(英文版)》2016,(1):24-30
The rate dependence of serrated flow and its effects on the stability of shear banding were systematically investigated in a prototypic bulk metallic glass.It was found that with the increase of external strain rate,the serra-ted flow is gradually suppressed and could completely disappear at a critical strain rate.The serration size,character-ized by the mean stress drop amplitude,decreases inversely with the strain rate,while the waiting time for serration decreases with the strain rate in a power-law manner.The rate dependence of the serrated flow has important effects on the dynamics and stability of shear banding process,and leads to an optimal plasticity achieved around the critical strain rate for the disappearance of serrated flow.These results are discussed and interpreted in terms of the mi-croscopic deformation theory and the stick-slip dynamics of shear banding for bulk metallic glasses. 相似文献