Chromium carbide coatings were grown on AISI O2 cold work tool steel via pack cementation method at the temperature of 900, 1000, and 1100 °C for 4, 6, 8h. The resulting coatings were examined using light microscopy LM, scanning electron microscopy/energy dispersive spectroscopy SEM/EDS, and X-ray diffraction XRD characterization techniques. The process produced chromium carbide coatings on a substrate with a thickness of up to 50 µm. The results indicated that the phase and layer thickness of the chromium coatings are highly dependent on the holding time and temperature. At low temperature (900 °C), the carbides coating appeared as one layer mainly consisting of Cr₇C₃ phase with thickness up to 13 µm. As the temperature rises to 1000 and 1100 °C, the carbides coating becomes two sublayers mainly consisting of Cr₇C₃ and Cr₂₃C₆ phases with thickness up to 50 µm. The microhardness value of the coating reached 1750 ± 45 HV_0.05 (17.16 GPa), which was higher than the 291 ± 2 HV_0.05 and 632 ± 4 HV_0.05 for the uncoated/annealed and the quench/tempered specimens, respectively. The activation energy for the process is 187 kJ/mol, and the kinetics of chromizing coating by pack cementation method revealed a parabolic relationship between carbide layer thickness and treatment time.

在 AISI O2 冷作工具钢上通过填充渗碳法在 900、1000 和 1100°C 的温度下生长碳化铬涂层 4、6、8 小时。使用光学显微镜 LM、扫描电子显微镜/能量色散光谱 SEM/EDS 和 X 射线衍射 XRD 表征技术检查所得涂层。该工艺在基材上产生了厚度高达 50 µm 的碳化铬涂层。结果表明，铬涂层的相和层厚度高度依赖于保温时间和温度。在低温（900 °C）下，碳化物涂层表现为一层，主要由 Cr ₇ C _{3 组成}相厚度可达 13 µm。随着温度升高到 1000 和 1100 °C，碳化物涂层变成两个亚层，主要由 Cr ₇ C ₃和 Cr ₂₃ C ₆相组成，厚度可达 50 µm。涂层的显微硬度值达到 1750 ± 45 HV _0.05 (17.16 GPa)，分别高于未涂层/退火和淬火/回火试样的 291 ± 2 HV _0.05和 632 ± 4 HV _0.05。该过程的活化能为 187 kJ/mol，通过填充渗碳法的渗铬涂层动力学揭示了碳化物层厚度与处理时间之间的抛物线关系。