Sand Casting Overview
The basic raw materials for sand making are foundry sand and sand mold binder. The most commonly used casting sand is silica sand. The high-temperature performance of silica sand cannot meet the requirements of special sand such as zircon sand, chromite sand, corundum sand, etc. In order to make the sand mold and core have a certain strength, and the metal liquid will not be deformed or damaged during the process of handling, molding and pouring, generally a molding sand binder is added in the casting, and the loose sand grains are combined with the molding sand. The most widely used sand binder is clay, which can also be used as a sand binder in various dry oils or semi-dry oils, water-soluble silicates or phosphates, and various synthetic resins.
The sand mold of the binder used in sand casting is divided into three types according to the type of sand and the way of building strength: clay wet sand mold, clay dry sand mold and chemically hardened sand mold.
