Carbon Kevlar, carbon aramid and other hybridization of composite laminates
carbon kevlar twill 2X2 210gr/sq.m
Carbon Kevlar is a term that is used to describe mixed type of reinforcing fiber for composite laminates, usually woven in fabric. This type of mixed fiber reinforcement is mostly referred to as “hybrid”.
Hybrid fabrics are a weaved mixture of two or more different types of fiber yarns. This mixing is generally utilized in order to take advantage of the good properties and characteristics of each reinforcement type, while at the same time mitigating the effects of their less preferable properties (synergy effect).
A similar synergy result could be obtained by two or more layers of the different materials, however on the other hand, hybrid fabrics also prevent or reduce the possibility of delamination. This happens because on hybrid fabrics the different type of yarns are woven into each other, thus making the whole thickness of the laminate skin material more uniform, (avoiding layers of different materials, that have different mechanical properties, with higher concentration of stress and mechanical loads at the point of surface contact of different material layers).
In applications where very thin, light weight hybrid laminates are required, a hybrid, carbon Kevlar fabric would allow the two types of fibers to appear in one single thin layer of fabric instead of two, alternating threads of each fiber in both directions, saving weight and reducing cost.
In other applications it is possible to have only one fiber running on the weft direction and the other on the warp direction. A laminate like this would exhibit carbon properties in one direction and Kevlar or aramid on the other. The special composites effect is called anisotropy. Anisotropy effect is greatly valued in most composite applications.
Carbon aramid hybrid constructions bear the high tensile strength and stiffness of carbon and the high impact resistance of aramid. Both fibers have low density and are relatively expensive. Carbon aramid hybrid fabrics are used in aerospace and marine applications, in construction, transportation, and for decorative purposes. An example of using hybrids in aerospace applications is to utilize the natural toughness of Kevlar to offset the brittleness of typical carbon fiber. Carbon aramid hybrids have low thermal stress compared to other (hybrids), increased modulus and compressive strength compared to 100% aramid design, and increased strength compared to full carbon design.
Hybrid fabrics are a weaved mixture of two or more different types of fiber yarns. This mixing is generally utilized in order to take advantage of the good properties and characteristics of each reinforcement type, while at the same time mitigating the effects of their less preferable properties (synergy effect).
A similar synergy result could be obtained by two or more layers of the different materials, however on the other hand, hybrid fabrics also prevent or reduce the possibility of delamination. This happens because on hybrid fabrics the different type of yarns are woven into each other, thus making the whole thickness of the laminate skin material more uniform, (avoiding layers of different materials, that have different mechanical properties, with higher concentration of stress and mechanical loads at the point of surface contact of different material layers).
In applications where very thin, light weight hybrid laminates are required, a hybrid, carbon Kevlar fabric would allow the two types of fibers to appear in one single thin layer of fabric instead of two, alternating threads of each fiber in both directions, saving weight and reducing cost.
In other applications it is possible to have only one fiber running on the weft direction and the other on the warp direction. A laminate like this would exhibit carbon properties in one direction and Kevlar or aramid on the other. The special composites effect is called anisotropy. Anisotropy effect is greatly valued in most composite applications.
Carbon aramid hybrid constructions bear the high tensile strength and stiffness of carbon and the high impact resistance of aramid. Both fibers have low density and are relatively expensive. Carbon aramid hybrid fabrics are used in aerospace and marine applications, in construction, transportation, and for decorative purposes. An example of using hybrids in aerospace applications is to utilize the natural toughness of Kevlar to offset the brittleness of typical carbon fiber. Carbon aramid hybrids have low thermal stress compared to other (hybrids), increased modulus and compressive strength compared to 100% aramid design, and increased strength compared to full carbon design.
aramid glass plain weave 250gr/sq.m
Other possible fiber combinations in hybrid composites are:
Conclusion:
Combining materials in composites manufacturing can optimize the overall performance of the final product. It can also affect cost as hybrid fabric may be less expensive compared to using only expensive fibers. For example, add a proportion of cheaper glass fiber to reduce cost of expensive composites with carbon fiber. Moreover, using hybrids allows even closer tailoring of composites properties to suit better desired requirements.
- Aramid-Glass: The high impact resistance and strength of aramid fiber combines with the good compressive and tensile strength of glass. The aramid glass laminate has also improved delamination resistance.
- Carbon-Glass: Carbon fiber exhibits high tensile strength and stiffness, glass reduces the cost, and this mix results in a strong material, with somewhat improved impact resistance at reasonable price.
- Hybridization by increasing carbon content in selected areas is used to increase strength or stiffness at this specific area, whereas with kevlar aramid, glass or other fiber material in carbon to make it locally softer.
Conclusion:
Combining materials in composites manufacturing can optimize the overall performance of the final product. It can also affect cost as hybrid fabric may be less expensive compared to using only expensive fibers. For example, add a proportion of cheaper glass fiber to reduce cost of expensive composites with carbon fiber. Moreover, using hybrids allows even closer tailoring of composites properties to suit better desired requirements.
