Carbon fiber is four times stronger than steel, and contains merely 1/4 of weight of iron, under the same dimension, while possessing features such as corrosion resistance, high temperature resistance, and high conductivity. Carbon fiber is extensively applied in auto, aerospace, and medical industries, though one major flaw of the fiber is that it oxidizes under extremely high temperature, for which scientists are seeking for low cost and solutions that can be expanded in scale.
Although most people wouldn’t encounter such issue in daily lives, it remains a challenge that must be resolved for the aerospace field. Yongfeng Lu, the Professor of Electrical Engineering at the University of Nebraska-Lincoln (UNL), commented that carbon fiber oxidizes under extreme temperature, and is prone to combustion when interacting with oxygen that resembles wood under a high temperature environment. Oxidization also rapidly depletes the extraordinary performance of carbon fiber.
Lu believes that the weakness of carbon fiber is that it is prone to combustion under an environment that is high temperature and filled with oxygen, and the resolution of these challenges, which reduces the flammability of carbon fiber that will avoid combustion, would derive positive results.
UNL has recently joined hands with the Institute of Condensed Matter Chemistry of Bordeaux on creating an extra protective layer for carbon fiber through a more effective method that is lower in cost.
The team first heated the salt to 982℃ to derive high heat molten salt, before it is added with chromium carbide (Cr3C2) and titanium carbide (TiC) to slightly increase the function of anti-oxidization, then finally immersed the carbon fiber into the molten salt mixture, which equips the fiber with three layers of protection with just one immersion. Lu pointed out that the team has successfully acquired multi-layer protection for carbon fiber under a single state.
The three layers of protection are able to effectively separate fiber and oxygen, and the further experiments also conformed to the anticipation of the team, where the carbon fiber maintained its structure under a high temperature and 1,200℃ and an oxyacetylene torch.
The next step of the study is to implement a comparison between the text group and the control group, and see how the new fire-proof coating works, as well as its endurance. Should the experiment succeed, it will become the first complex carbon fiber fire-proof technology that exempts exorbitant equipment, complicated procedures, and chemical reactions.
(Cover photo source: Flickr/Janak Raja CC BY 2.0)