flow behavior index

The flow behavior index, often called "n," describes how a material flows when subjected to stress. If n is about 1, the material behaves like a typical liquid, flowing smoothly under pressure. If n is less than 1, the material is shear-thinning, meaning it flows more easily as you stir or shake it—like ketchup. If n is greater than 1, it’s shear-thickening, becoming more resistant to flow when stressed—like a non-Newtonian fluid such as a cornstarch mixture. This index helps predict how materials respond under different forces, essential in industries like food processing, cosmetics, and manufacturing.