Height profiles spaced 0.008 um m apart across the fracture surface of TNT melt-cast in polycarbonate sleeves have been obtained with an atomic force microscope (AFM). Spatial power spectra (wavelengths of 0.016 um m to 4.0 um m) have been calculated using both a prolate spheroidal data window and a Kaiser window in the horizontal space domain prior to using a fast Fourier transform algorithm. Results based on topographical profiles across the surface include the following. The power spectral density of the individual fracture surface profiles is found to decrease with increasing spatial frequency over the dimensional region examined, approx approx 1.0 um m~-1 to approx approx 10.0 um m~-1. THe spectral amplitudes are found to have a frequency dependence proportional to f~s. The determined values of s in the dimensional region 1- 10 um m~-1 scatter in the range - 1 < s<-4. Those values of s outside the range -3<= s <= -2 indicate non-fractal fracture. There is significant structure in the spectra even for those with slopes within the range of a fractal dependence. Both observations are consistent with the appearance of numerous peaks in the spectra that indicate that a substantial amount of the fracture occurs at grain boundaries in the form of large clusters of TNT. Such a fracture process is deterministic.
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机译：使用原子力显微镜（AFM）获得了在聚碳酸酯套管中的TNT熔铸断裂表面上相距0.008微米的高度轮廓。在使用快速傅立叶变换算法之前，已使用水平空间域中的长球体数据窗口和Kaiser窗口计算了空间功率谱（0.016 um至4.0 um的波长）。基于整个表面的地形轮廓的结果包括以下内容。发现各个断裂表面轮廓的功率谱密度在所检查的尺寸范围内随着空间频率的增加而降低，从大约1.0 um m-1到大约10.0 um m-1。发现频谱幅度具有与fs成比例的频率依赖性。尺寸区域1-10 um m〜-1中s的确定值在-1 展开▼
