文章综述了我国科学工作者５０年来关于晶界弛豫研究的早期开拓和近期发展．前者包括扭摆内耗仪的发明、晶界内耗峰的发现和无序原子群晶界模型的提出．后者包括澄清了关于晶界内耗峰来源的争论，揭示了晶界弛豫具有一个临界温度，从而提出了一个适合于各种温度的综合的晶界模型．一个最重要的进展是关于竹节晶界内耗峰的发现与其机理的阐明，从而揭示了晶界附近的位错亚结构能够影响晶界本身的性质和结构．这对于研究多晶金属的力学性质提供了一个广阔的途径．另外，晶界与邻域位错的非线性交互作用的发现，为奠定非线性滞弹性这门新学科提供了实验基础 This article summarizes the early pioneering and recent development of the research on grain boundary relaxation in China over the past 50 years. The former includes the invention of torsional internal friction instrument, the discovery of the peak in the grain boundary and the proposal of the disorder atomic group grain boundary model. The latter includes a clarification of the debate over the source of peak wear in the grain boundaries, revealing that the grain boundary relaxation has a critical temperature, and thus a comprehensive grain boundary model suitable for various temperatures is proposed. One of the most important advances is the elucidation of the peaks and their mechanisms in the grain boundary of bamboo, revealing that the dislocation substructure near the grain boundaries can affect the nature and structure of the grain boundaries themselves. This provides a broad avenue for studying the mechanical properties of polycrystalline metals. In addition, the discovery of the non-linear interaction between the grain boundaries and the adjacent dislocations provides the experimental basis for laying a new line of nonlinear anelasticity