Optimizing Powder-to-Liquid Ratios in Lost Foam Casting Coatings: Impacts on Viscosity, Shear Thinning Behavior, Coating Weight, and Surface Morphology

Abstract

This study explores the effects of the powder-to-liquid ratio on the performance characteristics of lost foam casting coatings. The investigation focuses on how variations in this ratio affect key properties, including apparent viscosity, shear thinning behavior, coating weight, and surface morphology. Through a series of controlled experiments, coatings were prepared with different powder-to-liquid ratios and assessed for their physical and application properties. The results indicate that increasing the powder-to-liquid ratio raises the apparent viscosity and modifies shear thinning behavior. Notably, ratios exceeding 2.0 result in a sharp increase in viscosity that impedes coating application. The optimal powder-to-liquid ratio was determined to be between 2.0 and 2.2, where coatings demonstrated enhanced uniformity, improved particle distribution, and superior surface morphology. Coating weight increased up to a ratio of 2.2 but decreased beyond this threshold due to excessive viscosity. Both microscopic and macroscopic analyses confirmed that a ratio of 2.0 to 2.2 strikes the best balance for coating performance. These findings underscore the importance of precise powder-to-liquid ratio control to optimize the quality of lost foam casting coatings, offering valuable insights for refining coating formulations and application techniques in industrial contexts.