摘要
采用水冷铜模吸铸工艺制备出了片状Cu48Zr45Al7块体非晶合金。X射线衍射(XRD)表明,样品为完全非晶。利用差示扫描量热分析仪(DSC)在不同的升温速率下连续加热测得该片状非晶合金的热稳定性参数值,均随着升温速率的增加而增加,表明其玻璃转变和晶化行为均存在显著的动力学效应。运用Kissinger法计算出其玻璃转变温度激活能(Eg)、晶化温度激活能(Ex)和峰值温度激活能(Ep)分别为424.7kJ·mol-1,326.3kJ·mol-1和297.lkJ·mol-1。从热力学模型角度出发,对该合金的非晶形成能力进行了分析,计算出其混合焓ΔHchem=-25.55kJ·mol-1和归一化错配熵Sσ/kB=0.78。结果表明,该块体非晶合金具有较强的非晶形成能力(AFA)和良好的热稳定性。
Bulk amorphous slice specimen of Cu48Zr4l7 was prepared by using copper mould sorption cast process with water-cooling. X-ray diffi＇action （XRD） analysis indicates that the specimen is fully amorphous. The thermal stability parameters（Tg, Tx, Tp and △Tx） were obtained by using differential scanning calorimetry tester at different heating rates during the continuous heating with heating rate increasing, which indicate that both glass transition and crystallization have a significant kinetic effect. The activation energy of glass transition temperature （Eg）, crystallization temperature （Ex） and peak temperature （Ep） were determined by Kissinger plot method, respectively, 424.7 kJ·mol^-1, 326.3 kJ. mol^-1, 297.1 kJ·mol^-1, Thermodynamic properties and enthalpy relaxation of the bulk amorphous-forming liquid were investigated and the mixing enthalpy （△H^chem） and mismatch entropy （So/kB） calculated, the bulk amorphous alloy has △H^chem of -25.55 kJ· mo1^-1 and So/kBs of 0.78. The results show that the bulk amorphous slice specimen of Cu48Zr4l7 has high amorphous-forming ability （AFA） and favorable thermal stability.
出处
《热加工工艺》
CSCD
北大核心
2007年第22期44-47,共4页
Hot Working Technology
关键词
非晶合金
晶化
激活能
热稳定性
amorphous alloy
crystallization
activation energy
thermal stability
