China's carbon fiber production line thrives

With the launch of the country's first domestic large-scale high-performance carbon fiber production line in Shanxi province in November, China has made a major leap in materials science, moving from trailing global leaders to running alongside them in carbon fiber development, experts said.

The production line, jointly developed by the Institute of Coal Chemistry of the Chinese Academy of Sciences and Shanxi Huayang Carbon Material Technology Co, can produce 200 metric tons of high-performance T1000-grade carbon fiber annually. It is part of a long-term plan to reach an annual output of 1,000 tons.

Carbon fiber, an exceptionally strong, lightweight and versatile material, is widely used in aerospace, defense, automotive manufacturing and sports equipment. It serves as a key structural component in products ranging from spacecraft and military vessels to bobsled helmets and badminton rackets, enhancing performance while significantly reducing weight.

In 2024, China's demand for carbon fiber accounted for more than half of the global total. More than 80 percent of that demand was met by domestic production, a figure expected to rise to 90 percent by 2026, according to a carbon fiber industry report by Guoyuan Securities.

The mass production of T1000-grade carbon fiber, a new generation of high-strength material, is seen as a critical step in China's push to strengthen its energy security and develop emerging industries.

High-tech 'noodles'

Inside the Huayang Carbon Material Technology production facility in Datong, Shanxi province, rows of precision equipment operate continuously.

A spinning solution made from polyacrylonitrile is extruded through a spinneret with thousands of tiny holes, forming bundles of ultrafine filaments. The filaments then undergo oxidation and carbonization through automated systems. As they pass through sharply changing temperatures, their color shifts from milky white to golden yellow, dark brown and finally pure black.

"This production line manufactures T1000-grade carbon fiber, often referred to as the 'strongest material on Earth', with a carbon content exceeding 95 percent," said Zhang Shouchun, deputy director of the Institute of Coal Chemistry and leader of the T1000 development project.

The "T" in T1000 refers to tensile strength, with higher numbers indicating greater resistance to breakage. A single T1000 carbon fiber filament measures only 5 to 6 microns in diameter, less than one-tenth the thickness of a human hair, yet its strength is more than five times that of steel.

"A bundle of 12,000 one-meter-long T1000 carbon fibers weighs just 0.5 grams but can support more than 200 kilograms, roughly the weight of three adult men," Zhang said.

Compared with its predecessor, T800, T1000 offers a 10 to 20 percent increase in strength. The major improvement comes from a self-developed dry-jet wet spinning technology, said Jing Deqi, a senior engineer and technical development leader at the institute.

Traditional carbon fiber production mainly relies on wet spinning, in which the solution is extruded directly into a coagulation bath. While efficient, the method often produces uneven internal structures, limiting strength gains.

In dry-jet wet spinning, the solution passes through a short air gap after leaving the spinneret before entering the coagulation bath. During this stage, the material undergoes intense stretching and molecular alignment, producing a denser and more uniform internal structure that enables ultra-high tensile strength.

Jing likened the process to making Shanxi's traditional helao noodles, which are pressed through a perforated mold, briefly exposed to air and then dropped into boiling water.

Thanks to this technique, T1000-grade carbon fiber combines high strength with light weight, temperature resistance and corrosion resistance. It remains stable at temperatures ranging from 500 C in air to minus 180 C.

"It is typically used as a reinforcing material, combined with resins to form high-performance carbon fiber composites for aerospace, high-end equipment manufacturing and new energy applications," Jing said.

High-pressure gas cylinders made from carbon fiber composites, such as those used to store oxygen and nitrogen on space stations, commonly use T1000-grade fiber because of its light weight, high pressure tolerance and durability, he added.

Relay race

China's carbon fiber industry, with a history of more than five decades, has evolved from near-total reliance on imports to broad self-sufficiency, a process Zhang described as a relay race spanning generations of scientists.

In the 1970s, researchers at the Institute of Coal Chemistry broke through key technical barriers with limited reference materials, establishing China's first pilot production line for polyacrylonitrile-based high-strength carbon fiber to meet urgent national needs.

By the early 2000s, domestic demand for carbon fiber surged, but production technologies were tightly controlled by foreign companies. Strict export controls and technology embargoes severely restricted China's access to high-end carbon fiber, constraining the development of advanced equipment.

At the time, China paid extremely high prices for imported carbon fiber, sometimes reaching thousands or even tens of thousands of yuan per kg, said Lyu Chunxiang, a researcher at the institute.

In 2005, the institute was assigned an urgent task: to develop aerospace-grade T300 carbon fiber within three years, with qualified products due by June 30, 2008.

The challenge was formidable. Carbon fiber production involves long, complex processes spanning multiple disciplines, with numerous variables affecting final performance.

"There was almost no reliable information to draw on, and China had very few specialists in carbon fiber research," Lyu said. "Our Japanese counterparts took 15 years to achieve T300 production. We had only three."

Under intense pressure, Lyu's team worked long hours to design and refine production processes and develop key equipment, including polymerization reactors, spinnerets and steam drawing machines.

After repeated trials, the team delivered products that met all required standards, making China the third country, after Japan and the United States, to independently produce aerospace-grade carbon fiber.

Subsequent years saw steady progress. Despite continued embargoes, China achieved mass production of T700 and T800 grades.

In 2016, Zhang's team set out to establish stable, large-scale production technology for T1000-grade carbon fiber to support upgrades in aerospace and other high-end sectors. The focus was on developing dry-jet wet spinning technology and optimizing fundamental theories, core processes and domestically made equipment.

"Every step felt like crossing a river by feeling the stones," Zhang said, referring to technological blockades." But we were determined to push forward and develop a new generation of autonomous technologies."

Over a period of more than nine years, the team independently developed key technologies for T1000 and T1100-grade carbon fibers. Through in-depth optimization of core processes, they achieved international standards in strength and stiffness, while improving carbonization efficiency and product stability.

These advances laid the groundwork for large-scale demonstration projects, Zhang said.

Lab to industry

While mass production of T1000-grade carbon fiber is strategically significant for breaking foreign monopolies, translating laboratory results into industrial-scale output posed major challenges.

A collaboration between government, research institutions and enterprises proved critical.

In 2022, the Institute of Coal Chemistry signed an agreement with the Datong city government and the Huayang Carbon Material Technology, a traditional coal company undergoing a green transition. The partnership aimed to establish a high-performance carbon fiber production base in Datong and accelerate industrialization.

"Our institute formed a consortium with Huayang Carbon, transferring technologies and providing long-term technical support," said Cai Changta, deputy director of the institute.

Construction of the first-phase demonstration line, with an annual capacity of 200 tons, began in 2024. By November 2025, the line achieved stable mass production of T1000-grade carbon fiber.

Scaling up required careful attention to reliability and consistency, Zhang said. Carbon fiber production involves tightly coupled parameters, where minor adjustments can ripple through the system and affect product performance.

Before full operation, fluctuations in fiber stability were detected. Zhang and his team repeatedly inspected equipment, instruments and data, often making more than a dozen trips a day across floors in temperatures exceeding 40 C, before identifying and resolving the problem.

Through close collaboration, researchers and company staff overcame multiple challenges and ensured smooth progress, Zhang said.

Looking ahead, the institute hopes more companies will enter the carbon fiber sector and expand applications into areas such as construction and apparel.

"The carbon fiber market has enormous potential," Cai said. "The key challenge is reducing costs, which requires continuous technological innovation and a sufficiently large market to support reinvestment in new products."