Did You Know Strength & Stiffness Of A Material Are Different?

When many relate the strength and stiffness of a material, they actually mean different. Yes, that’s true.

Be it a paper, cardboard, metallic sheet, or any other material, measuring their strength and stiffness are two separate things. These are actually two crucial properties that help in evaluating the products for different applications, purposes, and requirements. However, a number of times people confuse both these terms as the same and also relate them with the hardness property of a material. But, since they are quite distinct terms, one must possess the knowledge of both of them to avoid errors. The following articles will walk you through the differences. Read on.

What Is The Strength Property Of A Material

Strength refers to the measure of the amount/degree of stress a material can resist or accommodate without getting broken or deformed. In other words, it defines the amount of maximum load a material can withstand before it breaks (tensile strength) or stop being in the original shape (yield strength). The tensile strength of materials like paper is often calculated with a paper tensile tester and likewise for other materials.

If the yield strength is more than the applied stress, the material gets back to its original shape when stress is removed. However, if the stress is more than the yield strength, then the material deforms and could not get back to its original shape after the stress is removed.

What Is The Stiffness Property Of A Material

Contrary to strength, stiffness is the measure of a material’s ability to bend when stress is applied while still returning to its original shape when stress is removed. It associates with the elastic deformation of the material and is therefore related to the elastic or flexible materials. The more flexible the material is, the less the stiffness.

For example, a rubber band, even after going through extreme forces returns to its original shape when the force is removed, hence its flexibility makes it less stiff. The applied stress or force to test the stiffness can be stretching, bending, or other strains. Moreover, materials can be tested for stiffness with a Taber stiffness tester.

Strength V/s Stiffness

The strength and stiffness properties of a material are not related directly:

1. The stiffness property of the material may allow it to return to its original shape even after the material takes a number of shapes while bearing the force. On the other hand, materials with high strength do not deform. They either resist the stress or deform permanently.

1. A low-strength material can easily break, while a low stiffness material can simply deflect high stress.

1. While a material can possess high strength it can have a low stiffness. In that case, it will break if the applied force exceeds the tensile strength.

1. A stiff material with low strength will deflect. This deflection will help the material resist the force and return to its original shape when stress is removed.

Conclusion

When it comes to testing the tensile strength and stiffness of paper, cardboard, and other materials, UECIN’s tester equipment and instruments prove extremely effective. Visit the website or get in touch to share inquiries.

Universal Engineering Corporation is an organization which designs and manufactures a wide range of testing instruments for pulp, paper & packaging industries