Why composites are becoming a better alternative to traditional steel
Improvements in the manufacturing technology of composites have greatly helped in gaining a foothold in the commercial market. New developments in the polymer resin matrix materials and high performance reinforcing fibers like fiberglass, aramid and carbon has also made composites as a more cost effective choice. A few years ago, the challenge in composite manufacturing was cost which was overcome through innovative manufacturing techniques. For certain applications, the use of composites like scotchply 1002 springs instead of the traditional metal springs have resulted in cost savings and a great reduction in weight. The type of construction of scotchply 1002 springs has minimized filament stress abrasion which is the reason why the life of conventionally reinforced plastics has been significantly shortened.
Furthermore, the need for composites made from lightweight but extremely strong fiber reinforcements and matrices with more seismic resistant structures has placed high emphasis in not only decreasing weight but on the ability to absorb shock and vibrations. The good thing with the manufacture of composites, its electrical and mechanical properties can be controlled through the choice of the right fiber reinforcement and the polymer resin. Composite properties like stiffness and thermal expansion can be varied continuously over a broad range of values that is under the control of the product designer.
There are different reinforcement materials that can be used for composites from Kraft cellulose paper, canvas cotton cloth, linen cotton cloth, fiberglass and many other materials. Careful selection of the reinforcement type will enable the designer to control the characteristics of the finished product so that it can be specifically tailored according to the application. Similarly, there is also a broad range of choice for polymer resins that will allow the composite to meet diverse design requirements. Some of the advantages of composites over traditional materials include:
- Higher tensile strength compared to steel or aluminum
- Improved torsional stiffness and impact properties
- Higher fatigue endurance
- 30% to 45% reduction in weight compared to aluminum that has been designed for the same structural requirements
- Composites are less noisy during operation and they provide lower vibration transmission than most metals
- Composites can be tailored to meet performance needs and complex design requirements which is not always possible with metals
- Longer life, reduced maintenance with excellent resistance to varying environmental conditions
- Composites have higher corrosion resistance and fire retardancy