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一、前言晶界对材料的高温和室温断裂、蠕变、腐蚀和偏析等行为起着重要的作用。不象位错、孔洞和裂纹等缺陷,晶界通常没有长程应力场,因而它对材料性能的影响主要取决于其核心的原子结构。然而,实验上难以把原子尺度的化学分析和结构观察结合起来,这使得大多数研究忽略了晶界结构的影响。早在1913年 Rosenheim 和 Humphrey就提出晶界是联接两个晶粒的非晶薄膜的假设,
I. Preface Grain boundaries play an important role in the behavior of materials such as high temperature, room temperature rupture, creep, corrosion and segregation. Unlike defects such as dislocations, voids and cracks, the grain boundaries generally do not have long-range stress fields and thus their effect on the properties of a material depends mainly on the atomic structure of their core. However, it is experimentally difficult to combine atomic-scale chemical analysis with structural observation, leaving most studies ignoring the effects of the grain boundary structure. As early as 1913, Rosenheim and Humphrey proposed that the grain boundary is the assumption that an amorphous thin film is connected with two grains,