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以展宽的激光束为加热源，在超高温度梯度条件下Ａｌ_72Ｎｉ_12Ｃｏ_16合金中获得了单相、十面体准晶定向生长组织．Ｘ射线衍射、透射电子显微镜、扫描电子显微镜和光学显微镜分析结果表明：在上述条件下定向凝固组织中为单相十面体准晶相；该相呈小平面形态并以侧向方式生长．十面体准晶中的周期性和准周期性的原子结构和熔池中的外延生长条件是影响生长形态的主要因素．实验结果与Ｔｏｎｅｒ原子结构生长模型预测相符．
With the widened laser beam as the heating source, single-phase and decagonal quasi-crystal directional growth structures were obtained in the Al_72Ni_12Co_16 alloy under ultrahigh temperature gradient. X-ray diffraction, transmission electron microscopy, scanning electron microscopy and optical microscopy analysis showed that: under the above conditions, the directional solidification structure is a single-phase decahedral quasicrystalline phase; the phase was a small plane and lateral growth. The periodic and quasi-periodic atomic structure in the decahedral quasicrystal and the epitaxial growth conditions in the melt pool are the main factors affecting the morphology of the growth. The experimental results are consistent with Toner atomic structure growth model prediction.