机械研磨Ti_x(Cu_(0.45)Ni_(0.55))_(94-x)Si_4B_2合金系的玻璃形成范围

GLASS-FORMING RANGE OF MECHANICALLY ALLOYED Tix(Cu_0.45Ni_0.55)94-xSi_4B_2 SYSTEM

利用X射线衍射、透射电子显微镜和差示扫描量热计分析表征了Ti_x(Cu_(0.45)Ni_(0.55))_(94-x)Si_4B_2(x=50,60,70,75,80)合金粉末高能球磨后产物的相组成,结果表明,合金成分在50≤x≤70范围,球磨产物主要为非晶相,但仍残留有α-Ti纳米晶体;当x>70％时,机械研磨仅导致初始晶体相的晶粒细化,形成纳米晶结构,未发生非晶化;不同Ti含量非晶相的晶化行为依赖于合金成分;用2％的V,Zr,Nb元素分别部分替代x=70和x=75合金中Ti时,对非晶相形成范围的扩展没有明显的作用。

Prealloyed powders with the nominal composition of Ti-x(Cu0.45Ni0.55)(94-x)Si4B2 (x=50, 60, 70, 75 and 80) were subjected to a high-energy ball milling. Phase formation in the final products was characterized using X-ray diffraction, transmission electron microscopy and differential scanning calorimetry. In the composition range of 50 less than or equal to x less than or equal to 70, the formation of amorphous phase is predominant, but the residual alpha-Ti nanocrystals still remains in the milled powders. When the Ti content exceeded 70%, the milling only leads to crystallite refinement to form the nanograined alpha-Ti and other phases. The crystallization behavior of the amorphous phases with different Ti content is, significantly concentration-dependent. The substitution of V, Zr and Nb of 2% for the element Ti in the two alloys of x=70 and x=75 has little effect on extending the glass-forming range of the system.