ABSTRACT In this study, a chromium carbide layer was fabricated by an in-situ casting technique on ductile iron cast components. The procedure consists of (i) applying a ferrochrome slurry at the surfaces of silica sand moulds to create a surface layer (e.g. coating) and (ii) use a ductile iron alloy to cast the coated moulds. The microstructure of the realised surface layer was characterised and analysed via Scanning Electron Microscopy (SEM), optical microscopy (OM) and X-ray Diffraction (XRD).The corrosion behaviour of the samples was analysed by an electrochemical method using 0.03 M NaCl. The wear tests and Vickers hardness measurements were performed to determine the properties of the surface layer. It was determined that the layer is composed of chromium carbide (Cr7C3), ledeburite and pearlite. The ‘chromium carbide’constituent improved significantly both the wear resistance and the hardness of the surface layer. Electrochemical measurements have indicated that the carbide-based layer exhibits a lower corrosion resistance than the substrate (e.g. casting).

中文翻译：

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通过创新的原位铸造技术生产的球墨铸铁表面改性

摘要 在这项研究中，碳化铬层是通过原位铸造技术在球墨铸铁件上制造的。该程序包括 (i) 在硅砂模具表面应用铬铁浆以形成表面层（例如涂层）和 (ii) 使用球墨铸铁合金铸造涂层模具。通过扫描电子显微镜 (SEM)、光学显微镜 (OM) 和 X 射线衍射 (XRD) 对实现的表面层的微观结构进行表征和分析。使用 0.03 M NaCl 通过电化学方法分析样品的腐蚀行为。进行磨损测试和维氏硬度测量以确定表面层的特性。确定该层由碳化铬 (Cr7C3)、莱氏体和珠光体组成。“碳化铬”成分显着提高了表面层的耐磨性和硬度。电化学测量表明，碳化物基层表现出比基材（例如铸件）更低的耐腐蚀性。