What is Deformation and Flow?

Materials (or continua) are generally classified as solids or fluids. Their main difference is that when subjected to external loading:

• a solid body will undergo time-independent deformation, and
• a fluid body will flow as a function of time.

     Materials that have both fluids and solids characteristics also exist. These include shear thickening materials such as custard (see Video), shear thinning materials such as blood, and other materials with time-dependent "visco" characteristics such as elastomers.

Video. The shear thickening effect of corn starch mixed with water.