Figure 11
The figure presents eight panels arranged in four rows and two columns, comparing surface morphology and elemental composition for four samples. The left column contains grayscale S E M micrographs labeled (a), (b), (c), and (d), and the right column shows the corresponding E D S spectra labeled (a 1), (b 1), (c 1), and (d 1). Panels (a)–(d) are S E M images, each including a scale bar labeled 10 micrometers at the lower right corner. Panel (a) shows a relatively smooth metallic surface with faint diagonal polishing marks and several small scattered bright spots that appear as minor surface defects or particles. Panel (b) displays a more uniform and smoother surface with very subtle texture and almost no visible defects. Panel (c) also exhibits a highly homogeneous surface with minimal contrast variation and only a few faint isolated spots. Panel (d) presents a similarly smooth and compact surface, slightly brighter overall, with extremely limited visible features, indicating a highly uniform morphology. Panels (a 1)–(d 1) present the E D S energy spectra corresponding to each S E M image. In all spectra, the horizontal axis is energy in kiloelectron volts ranging approximately from 0 to 15 with an interval of 5, and the vertical axis is labeled “c p s per electron volt”, extending from 0 to about 200 with an interval of 50. Each spectrum is dominated by strong iron (F e) peaks, with a major peak of about 200 near a low energy of 0.6 kiloelectron volts and another prominent F e peak of about 180 around 6.5 kiloelectron volts. In (a 1), F e shows the highest intensity, accompanied by smaller labeled peaks for M n, C r, V, S i, O, and C u. In (b 1), F e again dominates the spectrum, while M n, C r, V, S i, O, and C u appear as minor peaks at lower intensities. In (c 1), the elemental distribution remains similar, with strong F e signals and consistently smaller contributions from M n, C r, V, S i, O, and C u. In (d 1), F e continues to be the principal element, with comparable minor peaks from M n, C r, V, S i, O, and C u. Note: All numerical values and peak intensities are approximate.SEM images of Q235 steel specimens at 298 K under different concentrations of alkaline cleaning agents (a–d): (a) 5% cleaning agent, (b) 10% cleaning agent, (c) 15% cleaning agent,(d) 20% cleaning agent; EDS quantitative analysis (a1-d1), (a1) 5% cleaning agent, (b1) 10% cleaning agent, (c1) 15% cleaning agent, (d1) 20% cleaning agent. Source(s): Authors’ own work