基于含锆复合硅酸盐矿粉低碳钢树脂砂铸造防渗碳涂料

Anti-carburizing Coating for Resin Sand Casting of Low Carbon Steel Based on Composite Silicate Powder Containing Zirconium

采用X射线衍射分析仪、热膨胀测试仪、数字显微镜等研究了含锆复合硅酸盐矿粉的组成结构和性能特点。基于含锆复合硅酸盐矿粉的防渗碳涂料,在ZG1Cr18Ni9Ti不锈钢叶轮树脂砂铸造生产中的应用实例,采用直读式光谱仪、能谱分析仪研究了该涂料对铸件表层的防渗碳效果。采用扫描电镜观察了涂层在铸件浇注并冷却后的微观形貌变化,分析了该涂料的防渗碳作用机理。结果表明,该涂料具有优良的悬浮性、涂刷性、渗透性、流平性和抗裂性,涂层强度高,发气量小;铸件打箱时涂层绝大部分能成片剥离,铸件表面光洁,防粘砂效果优良。含锆复合硅酸盐矿粉涂料能代替纯锆英粉涂料,有效防止树脂砂低碳钢铸件表面粘砂和渗碳,显著改善铸造生产环境,降低铸造生产成本。

The structure and properties of composite silicate powder containing zirconium were investigated by X-ray diffraction analyzer, thermal expansion tester, digital microscope and other equipment. The application example of anti-carburizing coating based on the powder in the resin-sand casting of ZG1Cr18Ni9Ti stainless steel impeller. The anti-carburizing effect of the coating on the surface layer of the cast was studied by direct-reading spectrometer and spectrum analyzer. The change of the micro-structure of the coating after casting and cooling was observed by scanning electron microscope. The analysis of anti-carburizing mechanism of the coating was presented. The results show that the coating possess excellent suspension property, brush ability, permeability, leveling property and crack-resistance. The coating exhibits high strength and low gas evolution. Most of the coating could be automatically stripped off flakily when the casting is shaken out. Containing zirconium compound silicate mineral powder coatings can take place of pure zircon powder coating, effectively prevent the mild steel resin sand casting surface adhering sand and carburizing, significantly improve the casting production environment, reducing the casting cost of production.