Shearthickeningdilatant

Shearthickeningdilatant is a rheological term used to describe a type of non-Newtonian fluid that exhibits shear thickening behavior. This means that as the shear rate applied to the fluid increases, its viscosity also increases. In simpler terms, the fluid becomes thicker and more resistant to flow when agitated or stressed more intensely. The term dilatant is often used synonymously with shear thickening, referencing the tendency of these fluids to expand or dilate in volume under stress due to the rearrangement of particles.

Common examples of shearthickeningdilatant fluids include cornstarch mixed with water, often referred to as oobleck. When handled gently, oobleck flows like a liquid. However, if struck or squeezed rapidly, it becomes solid-like. This phenomenon occurs because at low shear rates, the cornstarch particles are well-lubricated by the water and can move past each other easily. At high shear rates, the particles are forced closer together, and the water is squeezed out from between them, leading to increased friction and a temporary solidification. Other examples include some colloidal suspensions and certain types of paint. The study of these materials is important in various fields, including material science, engineering, and even in the design of protective gear.