In brittle materials, these two values may be equal. Material strength is also discussed as ultimate or yield strength, expressed as a stress measurement. But for a raw material, it refers to the stress value causing permanent deformation. Regardless of the shapes of different components, if made from the same material, they will yield at the same stress value, even though the load values will be different. This characteristic of materials allows the predictive calculations that make design possible.
Material strengths vary over a wide range.
Steel can be extremely strong. Aluminum is usually somewhat weaker, although the material strength of some aluminum is higher than that of some steel. The strength of materials depends on composition and the processes used to prepare them- things like heat treatment and cold working. The strength values of all types of materials are catalogued and used by engineers in the design of products. Fundamentals of Design Optimization Density is a measure of weight per unit volume.