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用高温X射线衍射仪研究了纯铜,纯铝,Cu-Al,Al-Ni,Al-Fe,Al-Si等合金的熔体结构,发现Cu-Al,Al-Ni,Al-Fe合金熔体中除存在短程有序结构外,还存在中程有序结构.在纯金属铜、铝及Al-Si合金熔体中的不同温度范围内,只测取到了短程有序,没有发现中程有序结构.同时发现金属熔体中的这种中程有序结构的存在与消失是温度的函数.结构因子预峰是中程有序结构的表征.在铁含量分别为14％,16％和19％（质量分数,下同）的Al-Fe合金的结构因子曲线S（Q）上,温度为1550℃时,都存在预峰,即熔体中都存在中程有序结构.Al-35％Ni合金熔体温度在≤1300℃范围内,存在预峰;温度高于1400℃时,预峰逐渐消失.在Cu-12％Al合金熔体中,当温度低于1250℃时,结构因子曲线上18.5nm-1位置有预峰出现.随着温度的下降,预峰变得更加明锐.依据Cu-Al合金熔体结构测试结果,建立了中程有序结构模型.
The melt structures of pure copper, pure aluminum, Cu-Al, Al-Ni, Al-Fe and Al-Si alloys were studied by high temperature X-ray diffractometer. In addition to the existence of short-range ordered structure in the body, there is also a mid-range order structure in the pure copper, aluminum and Al-Si alloy melt in different temperature range, only detected short-range order, did not find the middle range Order a copy of this thesis It is also found that the existence and disappearance of this intermediate-order ordered structure in the metal melt is a function of temperature.The pre-peak of the structure factor is the characterization of the mesophase ordered structure.In the iron content of 14%, 16% And 19% (mass fraction, the same below) on the structural factor curve S (Q) of the Al-Fe alloy at 1550 ℃, there exists a pre-peak, 35% Ni alloy melt temperature in the range of ≤ 1300 ℃, pre-peak exists; when the temperature is higher than 1400 ℃, the pre-peak disappears gradually.In the Cu-12% Al alloy melt, when the temperature is lower than 1250 ℃, the structure The pre-peak appeared at 18.5nm-1 in the factor curve, and the pre-peak became more sharp as the temperature decreased.According to the test results of the melt structure of Cu-Al alloy, the mid-range ordered structure model was established.