Closed cell polymer foam skin thickness can be assessed by taking backscatter electron (BSE) images in a scanning electron microscope (SEM) at a series of accelerating voltages. Under a given set of experimental conditions, the electron beam mostly passes through thin polymer skin cell walls. That cell appears dark compared to adjacent thicker-skinned cells. Higher accelerating voltages lead to a thicker skin being penetrated. Monte Carlo modeling of beam-sample interactions indicates that at 5 keV, skin less than ∼0.5 μm in thickness will appear dark, whereas imaging at 30 keV allows skin thicknesses up to ∼4 μm to be identified. The distribution of skin thickness can be assessed over square millimeters of foam surface in this manner. Qualitative comparisons of the skin thicknesses of samples can be made with a simple visual inspection of the images. A semiquantitative comparison is possible by applying image analysis. The proposed method is applied to two example foams. Characterizing foam skin thickness by this method is possible using any SEM that is capable of collecting useful BSE images over a range of accelerating voltages. Imaging in low vacuum, where an electrically conductive metal coating is not required, leads to more sensitivity in skin thickness characterization.

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ɊȺȾɂɈɌȿɏɇɂɄȺ ɂ ɋȼəɁɖɍȾɄ 620. 169.2: 658.562.012.7 ȼ. Ⱥ. Ʉɭɡɧɟɰɨɜɚ, ɚɫɩɢɪɚɧɬ, ɂɠȽɌɍ ɢɦɟɧɢ Ɇ. Ɍ. Ʉɚɥɚɲɧɢɤɨɜɚ ȼ. ȼ. Ɇɭɪɚɜɶɟɜ, ɞɨɤɬɨɪ ɬɟɯɧɢɱɟɫɤɢɯ ɧɚɭɤ, ɩɪɨɮɟɫɫɨɪ, ɂɠȽɌɍ ɢɦɟɧɢ Ɇ. Ɍ. Ʉɚɥɚɲɧɢɤɨɜɚ ɉɊɈȽɇɈɁɂɊɈȼȺɇɂȿ ɋɈɏɊȺɇəȿɆɈɋɌɂ ɌȺɇɌȺɅɈȼɕɏ ɈɄɋɂȾɇɈ-ɉɈɅɍɉɊɈȼɈȾɇɂɄɈȼɕɏ ɑɂɉ-ɄɈɇȾȿɇɋȺɌɈɊɈȼ ɉɈ ȼɊȿɆȿɇɇɈɃ ɁȺȼɂɋɂɆɈɋɌɂ * ȼɜɟɞɟɧɢɟ ɞɧɢɦɢ ɢɡ ɜɚɠɧɟɣɲɢɯ ɯɚɪɚɤɬɟɪɢɫɬɢɤ ɧɚɞɟɠ-ɧɨɫɬɢ ɬɚɧɬɚɥɨɜɵɯ ɤɨɧɞɟɧɫɚɬɨɪɨɜ ɜ ɡɚɜɢɫɢ-ɦɨɫɬɢ ɨɬ ɧɚɡɧɚɱɟɧɢɹ ɢ ɭɫɥɨɜɢɣ ɷɤɫɩɥɭɚɬɚ-ɰɢɢ ɹɜɥɹɸɬɫɹ ɩɨɤɚɡɚɬɟɥɢ ɛɟɡɨɬɤɚɡɧɨɫɬɢ, ɞɨɥɝɨɜɟɱɧɨ-ɫɬɢ ɢ ɫɨɯɪɚɧɹɟɦɨɫɬɢ [1][2][3][4][5][6][7]. Ƚɚɦɦɚ-ɩɪɨɰɟɧɬɧɵɣ ɫɪɨɤ ɫɨɯɪɚɧɹɟɦɨɫɬɢ (Ɍ ɫJ ) -ɷɬɨ ɫɩɨɫɨɛɧɨɫɬɶ ɤɨɧɞɟɧɫɚɬɨɪɚ ɫ ɜɟɪɨɹɬɧɨɫɬɶɸ J ɫɨɯɪɚɧɹɬɶ ɫɜɨɢ ɫɜɨɣɫɬɜɚ ɜ ɭɫɬɚɧɨɜ-ɥɟɧɧɵɯ ɩɪɟɞɟɥɚɯ ɜ ɨɩɪɟɞɟɥɟɧɧɵɯ ɭɫɥɨɜɢɹɯ ɯɪɚɧɟɧɢɹ ɢ ɬɪɚɧɫɩɨɪɬɢɪɨɜɚɧɢɢ ɛɟɡ ɜɨɡɞɟɣɫɬɜɢɣ ɷɥɟɤɬɪɢɱɟɫɤɨ-ɝɨ, ɦɟɯɚɧɢɱɟɫɤɨɝɨ ɢ ɢɧɨɝɨ ɮɚɤɬɨɪɨɜ. ɋɨɯɪɚɧɹɟɦɨɫɬɶ ɤɨɧɞɟɧɫɚɬɨɪɨɜ ɩɪɨɜɟɪɹɟɬɫɹ ɩɭɬɟɦ ɩɪɨɜɟɞɟɧɢɹ ɢɫɩɵ-ɬɚɧɢɣ ɦɟɬɨɞɨɦ ɞɥɢɬɟɥɶɧɨɝɨ ɯɪɚɧɟɧɢɹ ɢɥɢ ɩɭɬɟɦ ɭɫ-ɤɨɪɟɧɧɨɣ ɨɰɟɧɤɢ [8].ɂɡɜɟɫɬɧɨ, ɱɬɨ ɤɚɱɟɫɬɜɨ ɢɫɯɨɞɧɵɯ ɦɚɬɟɪɢɚɥɨɜ [9, 10] ɩɪɢ ɢɡɝɨɬɨɜɥɟɧɢɢ ɩɪɨɦɵɲɥɟɧɧɵɯ ɢɡɞɟɥɢɣ ɨɤɚɡɵɜɚɟɬ ɫɭɳɟɫɬɜɟɧɧɨɟ ɜɥɢɹɧɢɟ ɧɚ ɢɯ ɧɚɞɟɠɧɨɫɬɶ, ɚ ɫɨɜɪɟɦɟɧɧɵɟ ɨɛɥɚɫɬɢ ɩɪɢɦɟɧɟɧɢɹ ɬɚɧɬɚɥɨɜɵɯ ɨɤɫɢɞɧɨ-ɩɨɥɭɩɪɨɜɨɞɧɢɤɨɜɵɯ ɤɨɧɞɟɧɫɚɬɨɪɨɜ ɩɪɟɞɴ-ɹɜɥɹɸɬ ɩɨɜɵɲɟɧɧɵɟ ɬɪɟɛɨɜɚɧɢɹ ɤ ɧɚɞɟɠɧɨɫɬɢ, ɩɨ-ɷɬɨɦɭ ɢɫɫɥɟɞɨɜɚɧɢɟ ɫɨɯɪɚɧɹɟɦɨɫɬɢ -ɨɞɧɨɣ ɢɡ ɯɚ-ɪɚɤɬɟɪɢɫɬɢɤ ɧɚɞɟɠɧɨɫɬɢ -ɹɜɥɹɟɬɫɹ ɧɟɨɛɯɨɞɢɦɨɣ ɡɚɞɚɱɟɣ.ɉɪɨɰɟɫɫ ɢɫɩɵɬɚɧɢɣ ɧɚ ɫɨɯɪɚɧɹɟɦɨɫɬɶ (ɫɪɨɤ ɫɨɯɪɚ-ɧɹɟɦɨɫɬɢ ɤɨɧɞɟɧɫɚɬɨɪɨɜ ɦɨɠɟɬ ɞɨɫɬɢɝɚɬɶ 25-30 ɥɟɬ) ɡɚɧɢɦɚɟɬ ɞɥɢɬɟɥɶɧɨɟ ɜɪɟɦɹ, ɩɨɷɬɨɦɭ ɞɥɹ ɨɰɟɧɤɢ ɤɚ-ɱɟɫɬɜɚ [11, 12] ɦɚɬɟɪɢɚɥɨɜ ɬɚɧɬɚɥɨɜɵɯ ɱɢɩ-ɤɨɧɞɟɧɫɚ-ɬɨɪɨɜ, ɧɟɨɛɯɨɞɢɦɨ ɩɪɢɦɟɧɟɧɢɟ ɭɫɤɨɪɟɧɧɵɯ ɦɟɬɨɞɨɜ ɨɰɟɧɤɢ. Ʉ ɭɫɤɨɪɟɧɧɵɦ ɦɟɬɨɞɚɦ ɨɰɟɧɤɢ ɫɨɯɪɚɧɹɟɦɨ-ɫɬɢ ɨɬɧɨɫɹɬɫɹ: ɦɟɬɨɞ ɦɨɞɟɥɢɪɨɜɚɧɢɹ, ɦɟɬɨɞ ɩɪɨɝɧɨ-ɡɢɪɨɜɚɧɢɹ ɩɨ ɜɪɟɦɟɧɧɨɣ ɡɚɜɢɫɢɦɨɫɬɢ ɢ ɦɟɬɨɞ ɩɪɨ-ɝɧɨɡɢɪɨɜɚɧɢɹ ɫɨɯɪɚɧɹɟɦɨɫɬɢ ɩɨ ɜɪɟɦɟɧɧɨɦɭ ɫɟɱɟ-ɧɢɸ.ȼ ɞɚɧɧɨɣ ɪɚɛɨɬɟ ɪɚɫɫɦɚɬɪɢɜɚɟɬɫɹ ɦɟɬɨɞ ɩɪɨɝɧɨɡɢ-ɪɨɜɚɧɢɹ ɩɨ ɜɪɟɦɟɧɧɨɣ ɡɚɜɢɫɢɦɨɫɬɢ [13] ɞɥɹ ɨɰɟɧɤɢ ɫɨɯɪɚɧɹɟɦɨɫɬɢ ɤɨɧɞɟɧɫɚɬɨɪɨɜ ɩɨ ɪɟɡɭɥɶɬɚɬɚɦ ɢɫɩɵ-ɬɚɧɢɣ ɩɪɢ ɞɥɢɬɟɥɶɧɨɦ ɯɪɚɧɟɧɢɢ ɜ ɭɫɥɨɜɢɹɯ ɨɬɚɩɥɢ-ɜɚɟɦɨɝɨ ɯɪɚɧɢɥɢɳɚ ɜ ɬɟɱɟɧɢɟ ɫɪɨɤɚ ɧɟ ɦɟɧɟɟ 0,25Ɍ ɫJ .ɂɫɯɨɞɧɵɟ ɬɪɟɛɨɜɚɧɢɹ ɉɪɢɦɟɧɟɧɢɟ ɪɚɫɱɟɬɧɵɯ ɦɟɬɨɞɢɤ, ɩɨɡɜɨɥɹɸɳɢɯ ɭɫɤɨɪɟɧɧɨ ɨɰɟɧɢɬɶ ɫɨɯɪɚɧɹɟɦɨɫɬɶ ɤɨɧɞɟɧɫɚɬɨɪɨɜ, -ɩɪɨɰɟɫɫ ɫɥɨɠɧɵɣ ɢ ɦɨɠɟɬ ɡɚɧɢɦɚɬɶ ɞɥɢɬɟɥɶɧɨɟ ɜɪɟ-ɦɹ (ɞɥɹ ɪɚɫɱɟɬɚ ɧɟɨɛɯɨɞɢɦɵ ɞɚɧɧɵɟ ɡɚ 25 % ɨɬ ɫɪɨɤɚ

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