Bentonite is a special mineral clay with viscosity, expansion, lubricity, water absorption and thixotropy and other characteristics, the use has covered casting materials, metallurgical pellets, chemical coatings, drilling mud and light industry and agriculture in various fields, later because of its wide use, known as “universal soil”, this paper mainly discusses the application and role of bentonite in casting.
Structural composition of bentonite
Bentonite is composed of montmorillonite according to its crystal structure, because its unique crystal has strong adhesion after water absorption, so it is widely used in casting sand, the sand is bonded together to form wet strength and plasticity, and dry strength after drying. After bentonite is dried, its cohesion can be restored after adding water.