前言 合金固溶体在低于一定的临界温度T_c时,可能出现原子的有序排列。有序化可能使合金的性能发生很大的变化。早在1923年,Bain等人用x光法证实了合金中原子有序排列的现象。长程有序合金的x光衍射花样上出现超结构衍射线。Warren系统地用x光来研究合金中有序相的晶体结构、有序度以及有序畴的尺寸,建立了比较完整的有序相变的x光衍射理论和测试方法。 用金相显微镜不易观察到长程有序的显微组织。Ogawa等人用x光衍射、电子 Preface Alloy solid solution below a certain critical temperature T_c, atomic ordering may occur. Orbitalization may make a great change in the performance of the alloy. As early as 1923, Bain et al. Confirmed the orderly arrangement of atoms in the alloy by the x-ray method. Superstructure diffraction lines appear on x-ray diffraction patterns of long-range ordered alloys. Warren systematically studied the crystal structure, ordered degree, and orderly domain size of the ordered phase in the alloy by x-ray to establish a more complete theory and test method of x-ray diffraction of ordered phase transition. It is not easy to observe long-range and orderly microstructure with a metallographic microscope. Ogawa et al. X-ray diffraction, electron