Zr-Cu-Ni-Al-Nb大块非晶合金的晶化行为、力学性能及电化学腐蚀行为的研究  

Crystallization, mechanical and corrosion properties of Zr-Cu-Ni-Al-Nb bulk glassy alloys

作　　者：柳林[1] 孙民[1] 谌祺[1] 刘兵[1] 邱春雷[1] 

机构地区：[1]华中科技大学塑性成型及模具技术国家重点实验室,武汉430074

出　　处：《物理学报》2006年第4期1930-1935,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:50471060);高等学校博士学科点专项科研基金(批准号:20030487015)资助的课题.

摘　　要：利用水冷铜模铸造法成功制备了Zr_(65-x)Cu_17·5)Al_(7·5)Ni_(10)Nb_x(x=0,2,5)大块非晶合金.X射线衍射、热分析研究结果表明,Nb的添加显著改变了非晶合金的晶化行为,促进了二十面体准晶相的形成.各合金的准静态压缩实验表明,Nb的适量添加有利于提高大块非晶合金的强度和塑性.其中x=5的大块非晶合金的抗压强度σb和塑性应变量εp分别达到1741MPa和5·0%.此外,还研究了不同成分的非晶合金在3%NaCl水溶液中的电化学腐蚀性能,发现各大块非晶合金均发生自钝化,钝化电流密度约为10-6—10-5A/cm2,远低于1Cr18Ni9Ti不锈钢.并且,随着Nb含量的增加非晶合金的点蚀电位不断增加,表明其耐腐蚀性不断增强.Zr65-xCu17.5Al7.5Ni10Nbx bulk metallic glasses （BMGs） with x = 0, 2 and 5 were prepared by water-cooled copper mold casting. X-ray diffraction and differential scanning calorimetry revealed that the addition of Nb changes crystallization pathway of the base alloy and promotes an initial formation of icosahedral quasicrystals. The mechanical properties of the BMGs prepared were measured with MTS in a mode of quasi-static compression. It was found that the addition of an appropriate amount of Nb significantly enhances the compression strength and plastic strain with the maximum value of σb = 1741 MPa and εp= 5.0% for the BMG containing 5at% Nb. In addition, the corrosion behavior of the BMGs was investigated in 3 % NaCl aqueous solution by electrochemical measurements. It showed that the BMGs with different compositions are all spontaneously passivated with passive current density of 10^-6-10^-5 A/cm^2, which is three order of magnitude lower than that of 1Cr18Ni9Ti stainless steel. The corrosion resistance of the BMGs can be further enhanced with the addition of Nb, as indicated by the increase in pitting potential with the inerease of Nb content.

关 键 词：ZR基大块非晶合金 晶化行为 力学性能 耐腐蚀性能 

分 类 号：TG139.8[一般工业技术—材料科学与工程] TG171[金属学及工艺—合金]