高能球磨形成具有明显玻璃转变的Ti_(50)Cu_(20)Ni_(24)Si_4B_2非晶态合金

FORMATION OF AMORPHOUS Ti_50Cu_20Ni_4B_2 ALLOY WITH A WELL-DEFINED GLASS TRANSITION BY HIGH-ENERGY BALL MILLING

在高能球磨作用下,名义成分为Ti50Cu20Ni24Si4B2的元素粉末混合物可通过固态反应非晶化.差示扫描量热分析（DSC）表明,球磨获得的非晶相在发生晶化转变之前出现明显的玻璃转变,过冷液态温度区间的宽度（△Tx）可达到57K.非晶态Ti50Cu20Ni24Si4B2合金加热时的晶化转变由一步完成.同时形成立方结构的（Ni,Cu）Ti相和其它未知相,为共晶型转变,随后发生晶化产物的进一步晶粒长大.非晶态Ti50Cu20Ni24Si4B2合金的约化玻璃转变温度（Trg）为0.56.

Under high-energy ball milling, elemental powder mixtures with a nominal composition of Ti50Cu20Ni24Si4B2 can be amorphized via solid state reaction. A well-defined glass transition before crystallization appears in the obtained amorphous phase during heating in a differential scanning calorimeter. A wide supercooled liquid region, DeltaT(x), is available to be about 57 K. Crystallization of the ball-milled amorphous phase proceeds through one step to form the (Ni, Cu)Ti phase with cubic structure and other unknown phases, which is a eutectic-type transition, followed by subsequent grain growth. The reduced glass-transition temperature of the alloy was determined to be 0.56.