Effects of the residual stress, interfacial roughness and scale thickness on the spallation of oxide scale grown on hot rolled steel sheet

In SituScanning Electron Microscopy Analysis of the Interfacial Failure of Oxide Scales on Stainless Steels and Its Effect on Sticking during Hot Rolling

“…The schematic images reveal the composition of the oxide scales on the basis of the EPMA analysis results and our previous work involving microstructural analyses. 13 The nanoindentation marks in the SEM images were used to analyze the variation in mechanical properties across the oxide/bulk interfaces and in the three equidistant regions (indicated by the red arrows) from the middle of the oxide scales, and the results are presented in Figure 6 .…”

“…The schematic images reveal the composition of the oxide scales on the basis of the EPMA analysis results and our previous work involving microstructural analyses. 13 The nanoindentation marks in the SEM images were used to analyze the variation in mechanical properties across the oxide/bulk interfaces and in the three equidistant regions (indicated by the red arrows) from the middle of the oxide scales, and the results are presented in Figure 6. studies, 15,24,25,27,28 showing that STSs with low and medium levels of Cr have oxide scales with composite-like distributions of Fe−Cr and Cr−oxide inclusions, while STSs containing high levels of Cr have oxide scales consisting of discrete and dense Fe− and Cr−oxide layers.…”

Corrosion behavior of typical hot rolled sheets in humid storage environments

“…Hot-rolled sheets have oxide scales on the surface of the steel plate during the rolling process. As the surface cooling water evaporates, the saline ions in the cooling water are adsorbed on the surface of the oxide layer (Noh et al, 2019). When the steel plate is stored in a humid environment, a small amount of water and saline ions together form a corrosive environment with concentrated saline ions, especially aggressive ions that induces pitting corrosion, Figure 6 The corrosion morphology of steels made by B manufacturer in test solution after rust removal such as Cl À .…”

“…Hot rolling is a typical metal steel plate manufacturing process, which improves the processing performance of metals by rolling at a temperature higher than the recrystallization temperature (Noh et al , 2019; Sellars and Whiteman, 1979; Jia et al , 2021). Typical representatives are structural steels (Q235 and X70) (Hwang et al , 2005; Zhang et al , 2019) The schematic diagram of the manufacturing process is shown in Figure 1 (Noh et al , 2019; Jha et al , 2012). During the process, the laminar cooling liquid is continuously sprayed on the surface of the steel to control the cooling rate (Mohapatra et al , 2014; Chakraborty et al , 2019).…”

“…Moreover, because of the high temperature of the steel plate during the hot rolling process, the laminar cooling water quickly evaporates on the surface of the steel plate. Therefore, the corrosive ions are enriched in scale of steel plates and, finally, exist in the surface oxide layer of the hot-rolled sheet in the form of crystalline salt (Noh et al , 2019; Jia et al , 2009; Chen and Yuen, 2001; Chen and Yuen, 2000, Liu, 2021), whose concentration is several times higher than that in the laminar fluid because of the enrichment effect (Chen and Yuen, 2000; Noh et al , 2019; Chen and Yuen, 2001; Spuzic et al , 1994; Zhang et al , 2021; Zhang et al , 2022). Therefore, when the steel plate is stored in a humid environment, these local salt deposits constitute a serious corrosive liquid environment, which leads to serious corrosion problems, especially pitting corrosion.…”