What is material strength and where can I use it?

*Written by: Dr. Jean Pierre Garcia, lecturer in the Production Engineering course at ESEG Faculty

Have you ever stopped to think about why a bridge doesn't collapse, how a building supports tons of weight, or even why your cell phone screen might break if dropped? It all relates to how materials react to everyday forces.

That's exactly where the strength of materials comes in: a essential area of engineering which studies how different structures and components behave when subjected to stresses such as tension, compression, bending, and shear.

More than just theory, this knowledge is present in practically everything around us, from simple objects to great works of art.

Understanding these concepts is not only important for engineers, but fundamental for ensuring safety, preventing failures, and developing more efficient and innovative solutions.

Throughout this content, you will discover how this area works in practice and where it applies in the real world.

What is Strength of Materials?

If you've ever wondered why a bridge doesn't collapse easily, how a building can withstand dozens of floors, or even why a simple charger cable doesn't break easily, you're already, without realizing it, witnessing the Strength of Materials.

This area of engineering studies how various materials behave when subjected to loads (forces and/or moments), or, in technical terms, how they react to the relationship between stress and strain.

In other words: what happens to a material when we pull, compress, twist, or bend it?

Below you'll find everything you need to know about the strength of materials!

Why is it so important in engineering and industry?

The main function of Strength of Materials is to ensure safety and reliability in the design of structures and structural elements. A poorly designed project can lead to serious and premature structural failures, often of a catastrophic nature.

In practice, engineers use safety factors to ensure the integrity of structures in the face of uncertainties, such as material variations, manufacturing errors, or unexpected conditions of use.

Furthermore, understanding the behavior of materials allows for cost reduction. An efficient project is not simply one that "doesn't break," but one that uses the ideal amount of material to fulfill its function safely and economically.

The pursuit of the best balance between dimensions, material, and cost results in high structural efficiency.

What does Strength of Materials study?

Throughout engineering training, this discipline introduces the different types of loads to which structural elements and structures may be subjected, such as:

• Tension and compression (axial loads): when an element is pulled or compressed. A concrete pillar, for example, works predominantly under compression, while elevator cables work under tension. .
• Shear: This occurs when forces tend to "cut" the material, such as in screws or rivets. .
• Flexion: This is very common in beams, where part of the structure is under tension and another part under compression simultaneously. .
• Twist: typical in transmission shafts, such as in motors and industrial machines. .

These phenomena are analyzed based on principles of Mechanics, such as the equilibrium of forces and moments, often using tools like the method of sections to identify internal forces in structures. .

Where is this knowledge applied?

In the automotive and aeronautical industries, reducing weight without compromising strength is essential for improving performance and efficiency. In aircraft, this is achieved through semi-monocoque structures, in which stringers, frames, and the skin itself work together to distribute loads.

In high-performance vehicles, such as racing cars, similar solutions are adopted in tubular chassis (space frame) and monocoque structures made of composite materials, such as carbon fiber. In these cases, the structure is designed so that its elements work predominantly in tension or compression, maximizing structural efficiency.

From an applied engineering perspective, these solutions represent a significant advancement in how materials are used, allowing for a reduction in structural mass without compromising the safety levels required in the design.

Read also: Where can a production engineer work?

How does engineering analyze these structures?

One of the most widely used tools in structural analysis is the diagram of internal stress resultants (normal force, shear force, and bending moment).

These diagrams illustrate how loads vary along a beam and therefore help the engineer identify critical sections with a higher risk of failure.

In a beam subjected to bending loads, the region where the bending moment reaches its maximum value tends to be the most critical from a structural point of view. In this section, the stresses are highest, increasing the risk of excessive deformation or material failure.

Therefore, it is precisely on these points that the engineer must focus the most attention during the sizing process.

And what does the strength of materials have to do with Production Engineering?

Although many associate Strength of Materials only with Civil or Mechanical Engineering, this Discipline is also fundamental in Production Engineering..

In Brazilian industrial practice, production engineers constantly deal with problems related to the structural performance of components, especially in environments with high utilization of machinery and equipment.

This is because the production engineer works directly with:

• Industrial processes (sizing of machines and equipment);
• Maintenance (failure analysis and component lifespan);
• Quality (guaranteed performance under real-world usage conditions);
• Innovation (development of new materials and solutions).

In typical industrial maintenance experiences, for example, it is common to analyze failures in shafts, gears, and metal structures, in which concepts such as fatigue, stress concentration, and overload are crucial for decision-making.

Conclusion

Strength of Materials is one of the cornerstones of modern engineering. It is present in everything from large infrastructure projects to small everyday devices.

More than formulas, it's about understanding how the physical world responds to loads and how to design safe, efficient, and innovative solutions.

For those considering a career in Production Engineering market, This is a clear example of how technical knowledge connects directly with industrial reality.

Want to create solutions that make a difference? Then come to ESEG College, part of the Etapa Group, and learn about the Production Engineering course.

Study at one of the colleges with the highest employment rates for its students. Visit our website and discover all our undergraduate programs!