7 Proven Methods to Identify Genuine vs. Fake Carbon Fiber Fabric and Ensure Structural Safety

In the field of structural strengthening, carbon fiber fabric has become a widely adopted key material due to its significant advantages: light weight, high strength, and construction efficiency (4-5 times faster than steel plate bonding). Its reinforcement principle involves bonding the fabric to the surface of concrete structural members using high-performance resin impregnating adhesive, fully leveraging the exceptional tensile strength of carbon fiber to enhance the load-bearing capacity and strength of the members.

However, the market is flooded with counterfeit carbon fiber fabrics, often made from dyed basalt fiber, aramid fiber, or similar substitutes. These inferior products fall far below standard performance levels. Not only do they fail to achieve the desired reinforcement effect, but they also pose serious safety hazards, potentially leading to engineering accidents. Therefore, accurately distinguishing genuine carbon fiber fabric from counterfeit versions is crucial.

Below are 7 practical methods to identify authentic carbon fiber fabric:

1、Inspect Appearance:

Genuine: Neat warp and weft weaving, free from significant defects like broken warps, broken wefts, or missing wefts. Carbon fiber tows are jet black with a glossy sheen, feel soft and lightweight to the touch, and exhibit uniform tow distribution.

Counterfeit: Dull, dry color, often showing uneven dyeing (especially noticeable in dyed basalt or aramid imitations).

2、Check Dimensions & Weight:

Genuine: Length deviation ≤ 1.5%, width deviation ≤ 0.5%. Unit area weight precisely meets standards; common specifications are 200g/m² (approx. thickness 0.111 mm) and 300g/m² (approx. thickness 0.167 mm). Weight is accurate and sufficient.

Counterfeit: Significant dimensional deviations, often underweight.

3、Genuine (for Structural Strengthening): Woven using 12k small-tow carbon fiber, ensuring good resin impregnation and bond strength.

Counterfeit: To reduce costs, often uses larger tows (15k, 18k, 24k, or even 36k, 48k) misrepresented as 12k. Large tows impede impregnation, resulting in poor bond quality and posing extremely high risks in structural strengthening.

4、Test Fire Resistance (Operate with Caution):

Genuine: Possesses excellent high-temperature resistance. Does not curl or melt when exposed to flame. May produce minor sparks while burning but self-extinguishes upon flame removal, with its form remaining largely unchanged. Shows no significant alteration even under prolonged exposure.

Counterfeit: Often combustible. Tends to curl, melt, or produce ash of abnormal colors (e.g., pale yellow, white) after burning. (WARNING: This test carries inherent risks. Strictly observe fire safety precautions!)

5、Measure Tensile Strength:

Genuine: Extremely high tensile strength. According to the Chinese National Standard GB 50367 "Code for Design of Strengthening Concrete Structures", Grade I carbon fiber fabric must have a tensile strength ≥ 3400 MPa, tensile modulus of elasticity ≥ 230 GPa (2.3×10^5 MPa), and elongation at break ≥ 1.6%. Difficult or impossible to break by hand.

Counterfeit: Tensile strength is far below standard; can often be broken by hand or with minimal force.

6、Verify Inspection Reports:

Genuine: Must possess valid certified test reports issued by authoritative testing institutions, proving compliance with standards such as GB 50728 "Technical Code for Safety Appraisal of Engineering Structure Strengthening Materials" and CECS 146 "Technical Specification for Strengthening Concrete Structures with Carbon Fiber Reinforced Polymer Laminate". These reports must verify key indicators like mechanical properties (tensile strength, modulus of elasticity) and durability.

Counterfeit: Lacks valid, compliant national/industry standard test reports, or reports contain questionable data.

7、Compare Price & Quality:

Genuine: High raw material costs and complex, stringent manufacturing processes mean the market price cannot be excessively low. Its performance (especially strength) is multiple times that of imitation fibers.

Counterfeit: Often attracts customers with prices significantly below reasonable market levels. May employ cost-cutting methods like blended weaving (mixing with cheaper fibers) or reducing material usage (skimping on tows). Red flag for ultra-low prices!

Conclusion: Selecting high-quality carbon fiber fabric is fundamental to ensuring the safety and effectiveness of strengthening projects. It is essential to meticulously apply the above 7 methods for identification. Never compromise quality for a lower price. Choosing counterfeit products can lead to irreversible, severe consequences where the cost far outweighs the savings. Consistently opt for products from reputable sources, backed by authoritative test reports and proven compliance with performance standards, to guarantee the long-term safety of building structures.