In this research, the irregular surface structure of 15 pure tungsten specimens that are irradiated respectively with 20, 40, 60, 80, and 100 shots of high-temperature deuterium plasma are under observation. The box-counting method is used to evaluate the scanning electron microscope (SEM) images taken from different locations within the same specimen. Obtained multifractal characteristics are then compared with the Fourier spectrum of stochastic relief. As a result, it is possible to determine the time dependence of surface damage with the box-counting method, but additional tests should be performed with the Fourier method to confirm this regularity. Besides, it has been studied further whether and how the fractal characteristics change with different magnifications within the same specimen. It was found that when selecting the appropriate magnification for SEM, X500 for a given specimen, the multifractal analysis of the arbitrarily selected image of surface damage well represents the average situation on the specimen.

本研究对15个纯钨样品分别用20、40、60、80和100次高温氘等离子体照射后的不规则表面结构进行了观察。计数法用于评估从同一样品内不同位置拍摄的扫描电子显微镜 (SEM) 图像。然后将获得的多重分形特征与随机浮雕的傅立叶谱进行比较。因此，可以使用盒计数方法确定表面损伤的时间依赖性，但应使用傅立叶方法进行额外测试以确认这种规律性。此外，还进一步研究了同一试样内分形特征是否随不同放大倍数的变化以及如何变化。