低弹bcc结构Ti-Mo-Nb-Zr固溶体合金的“团簇+连接原子”模型及其成分设计  

CLUSTER-PLUS-GLUE-ATOM MODEL AND COMPOSITION DESIGN OF BCC Ti-Mo-Nb-Zr SOLID SOLUTION ALLOYS WITH LOW YOUNG'S MODULUS

作　　者：马仁涛[1] 郝传璞[1] 王清[1] 任明法[2] 王英敏[1] 董闯[1] 

机构地区：[1]大连理工大学三束材料改性教育部重点实验室,大连116024 [2]大连理工大学工业装备结构分析国家重点实验室,大连116024

出　　处：《金属学报》2010年第9期1034-1040,共7页Acta Metallurgica Sinica

基　　金：国家自然科学基金项目50901012和50631010;国家重点基础研究发展计划项目2007CB613902资助~~

摘　　要：利用"团簇+连接原子"结构模型研究了典型低弹bccβ-Ti固溶体合金的成分特征.对现有低弹β-Ti固溶体合金的成分分析表明它们均满足团簇式[CN14团簇](连接原子)_x.根据该式,设计了Ti-Mo-Nb-Zr系列合金[MoTi_(14)]Ti(质量分数表达时为Ti-11.8Mo),[MoTi_(14)]Nb(Ti-11.2Mo-10.8Nb),[MoTi_(14)]Nb_2(Ti-10.1Mo-19.5Nb)和[Mo(Ti_(13)Zr)]Nb_2(Ti-9.2Zr-9.6Mo-18.7Nb),并采用Cu模吸铸快冷技术制备直径为3和6 mm的合金棒.结果表明,吸铸制备的合金均为bcc结构;当连接原子由Ti变成更低弹的Nb时,合金弹性模量降低;低弹Zr替代Ti进一步降低了合金的弹性模量,[Mo(Ti_(13)Zr)]Nb_2合金的弹性模量E=72 GPa.铸态样品经过固溶和水淬处理后弹性模量降低.The composition characteristics of typical bccβ-Ti solid solution alloys with low Young＇s modulus were analyzed by using the cluster-plus-glue-atom model,in which an alloy structure is dissociated into a cluster part and a glue atom part,i.e.isolated clusters are linked with glue atoms.The cluster here is the nearest neighbor coordination polyhedron with a coordination number of 14（CN14）.It is confirmed thatβ-Ti solid solution alloys with low Young＇s moduli satisfy a universal cluster formula[CN14 cluster]（glue atom）_x given by this model.Alloys,described by cluster formulas[MoTi_（14）]Ti,[MoTi_（14）]Nb,[MoTi_（14）]Nb_2 and[Mo（Ti_（13）Zr）]Nb_2,Ti-11.8Mo（mass fraction,%）, Ti-11.2Mo-10.8Nb,Ti-10.1Mo-19.5Nb and Ti-9.2Zr-9.6Mo-18.7Nb were designed and the alloy rods with diameters of 3 and 6 mm were prepared by copper-mould suction-cast method,respectively. These suction-cast alloys possess monolithic bccβ-Ti structure.The introduction of low-modulus Nb as glue atoms weakens the cluster linking and decreases the Young＇s modulus.Further substitutions with low-modulus Zr reduces the Young＇s modulus to 72 GPa in the[Mo（Ti_（13）Zr）]Nb_2 alloy. Solution treatment plus subsequent water quenching decreases slightly the Young＇s moduli of the suction-cast alloys.

关 键 词：Ti-Mo-Nb-Zr合金 β-Ti固溶体 “团簇+连接原子”结构模型 成分设计 低弹性模量 

分 类 号：TG146.2[一般工业技术—材料科学与工程] TG113.12[金属学及工艺—金属材料]