U-Co系非晶合金的形成与耐蚀性研究  

STUDY ON FORMATION AND CORROSION RESISTANCE OF AMORPHOUS ALLOY IN U-Co SYSTEM

作　　者：黄火根[1] 王英敏[2] 陈亮[1] 蒲朕 张鹏国[1] 刘天伟[1] 

机构地区：[1]中国工程物理研究院,绵阳621900 [2]大连理工大学材料科学与工程学院三束材料改性教育部重点实验室,大连116024

出　　处：《金属学报》2015年第5期623-630,共8页Acta Metallurgica Sinica

基　　金：国防基础科研计划项目B1520133007;中国工程物理研究院科技发展基金项目2013A0301015资助~~

摘　　要：将U-Co二元系中的富U合金UxCo100-x（x=50∽87.5）作为研究对象,采用电弧熔炼与甩带方法制备它们的母合金锭与薄带样品,通过XRD和DSC研究合金样品的相组成与稳定性,同时采用动电位极化方法研究非晶合金的耐腐蚀性能.结果表明,条带非晶形成的成分区间为58.5≤x≤78,其最佳成分出现在U66.7Co33.3附近;在20 K/min加热速率下,U-Co非晶的晶化温度位于534∽550 K之间,晶化放热焓为4.8∽8.5 k J/mol,约化晶化温度Trx值最高达0.535;在50×10-6Cl-溶液中,U-Co非晶合金的腐蚀电位大都接近-50 m V,其抗腐蚀能力显著优于贫铀,且U-Co非晶耐腐蚀性与其形成能力显示出正相关性.The formation of amorphous phase has been investigated in U- Co system over a wide range of compositions, namely, UxCo100-x（x=50∽87.5） by mean of melt-spinning. Phase identification for the arc-melted ingots and rapidly quenched alloys, and the thermal stability of the amorphous phases thus formed have been examined by XRD and DSC, respectively. The component phases in the ingot alloys were structurally the same as those presented in U- Co phase diagram, but were associated with a certain compositional metastability. Rapid quenching experiment revealed that the ease of formation of amorphous phase occurred within the composition range of 58.5≤x≤78, and amorphous phase was most readily formed in the vicinity of U66.7Co33.3composition. The dynamical crystallization temperatures of the amorphous phases were determined to be 534∽550 K at a DSC heating rate of 20 K/min, and the highest reduced crystallization temperature（relative to the liquidus temperature） as calculated to be 0.535, and moreover, the exothermal enthalpies of crystallization were determined to be in a range of 4.8∽8.5 k J/mol. Upon room temperature electrochemical polarization in a 50 × 10- 6Cl-electrolyte, these amorphous alloys exhibited corrosion potentials as high as about- 50 m V, being much more positive than that of depleted uranium. In these amorphous alloys, it has also been found that the rust resistance performance appears to be parallel to the ease of amorphous phase formation.

关 键 词：非晶合金 铀合金 快速凝固 耐腐蚀性能 

分 类 号：TG13[一般工业技术—材料科学与工程]