Solidifying incongruently melting intermetallic phases as bulk single phases using the example of Al2Cu and Q-phase in the Al–Mg–Cu–Si system
Solidifying incongruently melting intermetallic phases as bulk single phases using the example of Al2Cu and Q-phase in the Al–Mg–Cu–Si system
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DOI：
10.1016/j.jallcom.2011.11.119
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发表时间：
2012-02
影响因子：
6.2
通讯作者：
A. Löffler;J. Gröbner;M. Hampl;H. Engelhardt;R. Schmid-Fetzer;M. Rettenmayr
中科院分区：
文献类型：
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作者：
A. Löffler;J. Gröbner;M. Hampl;H. Engelhardt;R. Schmid-Fetzer;M. Rettenmayr
对Al-Cu-Mg-Si系四元合金进行了平面前定向凝固实验，制备了不完全熔化的金属间相，特别是二元Al2Cu相和四元相（“q相”）。通过这种方法，生成仅由单相组成的批量样品。得到了100%单相Al2Cu和95% q相的样品切片。用能量色散x射线光谱（EDX）测定了q相的组成。测量的浓度接近最近通过从头计算预测的最稳定的al3cu2mg9si7组成。用差示扫描量热法（DSC）测定了Q→L+Mg2Si+(Si)反应的包晶温度为703℃。考虑到测得的成分和包晶温度，对calphhad数据库进行了优化。为了验证优化后的数据库，进行了Scheil计算，并与实验确定的凝固相顺序进行了比较。
Plane front directional solidification experiments were carried out for preparing incongruently melting intermetallic phases in the quaternary alloy system Al–Cu–Mg–Si, particularly the binary Al2Cu phase and the quaternary phase (“Q-phase”). By this method, bulk samples that consist of only a single phase are generated. Sample sections consisting of 100% single phase Al2Cu and of 95% Q-phase, respectively, were obtained. The composition of the Q-phase was measured by Energy Dispersive X-ray Spectroscopy (EDX). The measured concentrations are close to the Al3Cu2Mg9Si7composition that has recently been predicted as most stable by ab initio calculations. A peritectic temperature of 703°C for the reaction Q→L+Mg2Si+(Si) was determined by differential scanning calorimetry (DSC). An optimization of the Calphad database was performed considering the measured composition and peritectic temperature. For validating the optimized database, Scheil calculations were performed and compared with the experimentally determined sequence of solidifying phases.