The Eiffel Tower is a true triumph of steel construction. Completed in 1889, the iconic Parisian landmark consists of more than 18,000 individual steel pieces and is still a major draw for visitors from all over the world. 7,300 tons of steel were installed by Gustave Eiffel and his men, who created an airy and durable construction from this strong, workable metal. For more than 130 years, the "Old Iron Lady" has withstood the hardships of the weather, world wars and up to 32,000 pairs of feet a day.
What Eiffel knew in 1889 remains undisputed to this day: if you're looking for a material with a wide range of advantages for a wide range of components suitable for a wide variety of applications, it's hard to beat steel. Nevertheless, steel also has its disadvantages and may not always be the best choice. Let's have a look at some of the main pros & cons of this durable metal.
Advantages of Steel for Designers & Product Developers
- Static Load Capacity & Elasticity:
Steel constructions usually have a high static load-bearing capacity that maintains integrity over long periods of time. For example, vertical supports in open air photovoltaic systems have to carry heavy loads and withstand strong environmental influences over many years and through all seasons. Due to the high elasticity of steel, the raw material is used wherever a high load-bearing capacity is needed over larger areas. For example, when the plenary hall of the Reichstag in Berlin was equipped with a bulletproof glass facade, steel was the only choice that could support this heavy and thick glass front spanning such a large distance.
- Longevity:
Steel as a raw material is extremely durable, but of course not immune to all external influences. Even the Eiffel Tower has had to be protected against the effects of corrosion with a special coating on several occasions. With some steels, this corrosive reaction is even intentionally provoked, such as with weatherproof Corten Steel (“Corten” is the brand name). This is particularly popular in building construction for aesthetic-decorative purposes inside and out, since the phosphorus-containing steel alloy has a surface rust effect without rusting through completely or affecting its integrity. This oxide layer functions as a protective layer, helping give the components a long service lif
- Dynamic Stress:
Steel is also a popular material for production components, since it's hard, strong, and durable – it shows little or no signs of fatigue. High resistance to dynamic stress is particularly important where parts are subject to both high and low cyclic loads, such as hydraulic components.
- Variety of Alloys:
Steel can be excellently reproduced with the help of alloys and optimized for a wide variety of applications. Today, high-strength alloys are used for crash absorption elements in the automotive industry. These and other forms of quality steel often arise due to new requirements associated with modern innovations. Manufacturers in the steel industry are constantly outperforming each other and looking to innovate – Welser Profile included.
- 100% Recyclability:
Unlike aluminum, steel has an unlimited life cycle and is therefore 100% recyclable. Current research and initial production developments are starting to focus on Green Steel, looking to make the use of steel a sustainable trend for the future.
- Thermal Expansion Coefficient:
Anyone who has ever heard buildings creak and groan in high heat knows that ghosts aren't the ones to blame. When the sun is beating down on curtain walls at 40-50°C, having the right material is important: the thermal expansion of aluminum, for example, is much higher than that of steel.
- High Fire Resistance:
Steel is also the ideal material for fire resistant components and fire protection doors: when fire breaks out, its resistance is relatively high. If a fire breaks out anywhere in or on the building, aluminum, for example, collapses relatively quickly, while steel parts can withstand the blazing flames for a long time without deforming directly under the enormous heat.
- Variety of Grades:
More than 2,500 types of steel are now on the market, ranging from structural steels to (un)alloyed steels, tool steels and high-strength steels to stainless steel and special steels. In many cases, the material properties of the individual steel grades match the individual requirements that designers and product developers have for their components. And the efforts of the steel manufacturers are far from over.
- High Availability:
Despite the much-cited scarcity of raw materials in recent times, the material supply for steel is quite high, especially in Central Europe. Steel suppliers and steel processing companies are also sufficiently represented, meaning that conventional steels are usually available at any time.
Disadvantages of Steel for Designers & Product Developers
- Weight:
Steel as a material has a higher dead weight than aluminum (for example). However, due to the strength and high elasticity of steel, the weight disadvantage can be minimized by reducing material thickness.
- Corrosion Protection:
In many environments, bare steel is significantly less resistant to corrosion than aluminum. Profiles with open surfaces and edges, for example, have no protection against corrosion and need to be protected with an additional coating.
- Processing:
Due to its high strength, it's more difficult to further process steel after production. Carbide tools are required for subsequent sawing, milling or punching - these are relatively expensive, and wear out more quickly. The advantage of roll-formed steel components is that hole punching, surface processing and separating cuts can be integrated directly into the system.
- Perceived Cost:
This is not necessarily an actual disadvantage, but a perceived one that has a negative effect: steel might be ruled out early on even though it might have been the best material for the component in question. Many designers and product developers still believe that steel is more expensive than the alternatives. In reality, the cost calculation is dependent on so many factors that in individual cases, steel may surprise you by being the more cost-effective option in the long term.
Steel in Roll Forming
In roll profiling (also called roll profiling), a steel strip wound into a coil is fed through various rollers in the plant, which ensure the desired form. Additional process and finalization steps such as stamping and welding enable a wide variety of functionalities of the respective component in just a few production steps. The combination of the durable, robust material and the flexible, sustainable process has real potential for construction and product development:
- Function-related perforations, punches and embossing are possible right from the first manufacturing process, directly on the system.
- Even with high-strength steels, complex cross-sections can be manufactured with tight tolerances.
- Forming is possible even if decorative surfaces already exist.
- Roll forming enables cost-effective production of closed profile cross-sections (laser or HF-welded profile tubes and special tubes).
7 Questions to Help Determine Whether Steel is the Right Material for Your Component
Here are some basic questions that, although they might not immediately provide a clear answer for every component, should give you an initial indication of whether looking at steel for your new component is worthwhile. Let's see how many questions you answer YES to:
- Does CO2-reduction help with my company's climate goals?
- Does my component need to have high strength?
- Does my component have to withstand high heat?
- Does my component have to withstand high torsional forces?
- Should my component last longer than 5 years?
- Does my component have to be wear-resistant?
- Does my component have to be light and strong at the same time?
Conclusion: Steel YES or NO?
Deciding on steel is not only deciding on the material: it's also a decision that will help determine how your company meets the challenges of the future. Especially in the context of development, innovation and sustainability are increasingly going hand in hand. Steel is, for example, more resource and energy-efficient than aluminum, while also offering a wide range of possible applications – some of which we may not even have thought of yet. Thanks to the roll forming process, numerous additional functions can be integrated into a component without immediately causing production costs to skyrocket.
If you answered YES to at least 4 out of the 7 questions about steel for your new component, why not get in touch with us for an informative, no-commitment chat? We'd be happy to hear from you.