The greater the difference in concentration, the quicker the rate of diffusion. The higher the temperature, the more kinetic energy the particles will have, so they will move and mix more quickly. The greater the surface area, the faster the rate of diffusion.

A change of state is the change of a substance from one physical form of matter to another. When a substance undergoes a physical change, it does not change its identity, just its appearance. Energy is Gained and Lost. To change a substance from one state to another, energy must be added or removed.

Many factors can affect the rate of diffusion, including, but not limited to, concentration gradient, size of the particles that are diffusing, and temperature of the system. In living systems, diffusion of substances in and out of cells is mediated by the plasma membrane.

Changing material properties Processes such as mixing, heating and cooling can change materials and their properties. This can be useful as the new properties may be better suited for particular purposes. For example, mixing certain metals can create a material that is both strong and lightweight.

For the majority of materials, the yield strength decreases with increasing temperature. In metals, this decrease in yield strength is due to the thermal activation of dislocation motion, resulting in easier plastic deformation at higher temperatures.

Higher tempering temperatures tend to produce a greater reduction in the hardness, sacrificing some yield strength and tensile strength for an increase in elasticity and plasticity.

According to the research, in general, with increasing temperature, the tensile strength (in constant strain rate) decrease, and the softness increases [29]. The higher deformation temperature makes the grain size larger, and dislocation density decreases.