Foundry Grade Bentonite refers to a type of bentonite clay that is specifically used in the foundry industry for various applications, particularly in the casting of metal parts. Foundry grade bentonite is characterized by its ability to provide good binding and bonding properties to the molding sand used in the casting process. It helps to create molds and cores that maintain their shape during the pouring of molten metal and allow for the easy removal of the finished castings.

The properties of Foundry Grade Bentonite can vary based on the specific deposit and processing methods used, but generally, it exhibits the following characteristics:

Swelling and absorption:
Bentonite clay has a high capacity to absorb water and swell, which makes it effective in forming a stable and solid molding sand mixture.

Thixotropy:
Foundry grade bentonite exhibits thixotropic properties, meaning it becomes more fluid when agitated but returns to a more viscous state when left undisturbed. This property helps in even distribution and compacting of the molding sand.

Plasticity and cohesion:
The clay’s plasticity allows it to be molded into various shapes easily. Its cohesive nature helps maintain the integrity of the sand mold or core during handling and pouring.

Thermal stability:
Bentonite is able to withstand the high temperatures encountered during the metal casting process without undergoing significant changes.

Bonding and adhesion:
Bentonite forms a strong bond with the sand particles, providing the necessary strength to the molding sand mixture.

Compatibility:
It should be compatible with other additives and binders commonly used in foundry applications.