Composites vs Steel

Composite usage in almost all industries is rapidly increasing depending on the new developments in composite materials technology in the last decades. With these developments, the market share of composite materials in the industries attracts significant attention for the future. Furthermore, It is also thought that composite materials will replace steel and most of its derivatives in the coming years because of the benefits of composite materials.

What makes composites replace over steel?

As the definition of composite materials implies, composite materials formed from two or more separate materials to achieve increased material properties and characteristics in the desired area. Basically, composites improve material properties for the conventional parts used in the industry. The most well-known feature of composites is the weight of course. Composites are mostly used to gain efficiency by reducing the overall weight by replacing over steel and metals.

When steel is considered, composite materials are far more beneficial for general applications in the industry. Composites can have up to 70% reduced weight compared to steel while exhibiting higher stiffness to weight ratios. Considering only these properties, composite materials are used in many applications in the industry to take advantage of these characteristics. There are much more advantages of composite materials as well as much more composite material combinations.

The graphic is for reference purposes only. Numbers values are for proportional comparison.

Main Advantages of Composites

As explained above, composites can have different strong characteristics depending on the involved materials. Therefore, some of the most commonly used properties against steel are covered and listed below:

  • High Stiffness to Weight Ratio: Composites can have higher stiffness to weight ratio than steels while providing up to %70 lighter weight. Carbon fiber mostly commonly preferred for this type of application.
  • Corrosion: Corrosion may become a significant problem for steel in applications and these problems need to be solved with coatings or maintenance. Composites are naturally anti-corrosive and can easily stand up against corrosive conditions and this provides long-term performance.
  • Thermal Properties: Composite materials can perform lower thermal expansion than steel and this relates that more stable behavior can be achieved in the different temperatures. For example, steel has heat an expansion rate of roughly third times over carbon fiber epoxy.
  • Conductivity: Composites do not interact with electricity while metals like steel do. This makes composite materials an important alternative for many applications in different industries. The most common insulators in the industry are glass fiber composite parts.