Ningbo Institute Of Materials Breaks Through The Preparation Technology Of M65j High Strength And High Modulus Carbon Fiber

Recently, Ningbo Institute of materials, Chinese Academy of Sciences announced that it has achieved another major breakthrough in the field of domestic high strength and high modulus carbon fiber, successfully developed CNI qm65 (m65j grade) high strength and high modulus carbon fiber, and formed the small batch production capacity of domestic m65j carbon fiber.

High strength and high modulus carbon fiber has a series of advantages, such as high tensile modulus, small coefficient of thermal expansion, stable size and so on.

At present, among the pan based high strength and high modulus carbon fibers abroad, the two models with the highest tensile modulus are: m65j carbon fiber developed and produced by Toray, Japan, with a tensile modulus of 640gpa and a tensile strength of 3.50gpa, and um68 carbon fiber developed and produced by Diren company of Japan, with a tensile modulus of 650gpa and a tensile strength of 3.33gpa.

According to an industry insider, m65j and um68 represent the highest level of PAN based high strength and high modulus carbon fiber preparation technology in the world, but they have not yet been commercialized. At present, the highest modulus PAN based carbon fiber that has been successfully commercialized is m60j carbon fiber from Toray, Japan, with a tensile modulus of 588gpa.

From the perspective of China's market, in recent years, through the efforts of many scientific research institutes and leading enterprises, the preparation technology of high strength and high modulus carbon fiber in China has developed rapidly and made new breakthroughs.

In January 2016, Ningbo Institute of materials achieved a major breakthrough in the preparation technology of domestic m55j carbon fiber; in September of that year, the preparation technology was verified, and the high strength and high modulus carbon fiber with tensile strength of 4.15gpa and tensile modulus of 585gpa was obtained; subsequently, the continuous and stable production of domestic m55j high strength and high modulus carbon fiber was further realized, and the inter batch dispersion coefficient of fiber main performance was far less than 5 %。

In 2018, the 863 project "key technology research on Graphitization of polyacrylonitrile carbon fiber" undertaken by the carbon fiber engineering technology research center of Beijing University of chemical technology, together with Weihai development Fiber Co., Ltd., aerospace materials and Technology Research Institute and Beijing satellite manufacturing factory Co., Ltd., successfully passed the acceptance. After three years of collaborative research, the project has overcome the key technologies of fiber preparation, fiber performance characterization, fiber application and the design and preparation technology of high temperature graphitization equipment for carbon fiber. The performance indexes of carbon fiber and its composite materials developed are equivalent to those of imported m55j carbon fiber.

This breakthrough marks the complete localization of qm4055 (m55j) high strength and high model carbon fiber materials in China from process to equipment, and improves the independent support ability of high strength and high modulus carbon fiber in China's aerospace application field. Therefore, the company has expanded the production capacity of high strength fiber M55.

"The breakthrough of m55j preparation technology and engineering technology has attracted the attention of relevant Japanese enterprises. A person in charge of the industry is in charge of a Japanese company. " One carbon fiber practitioner said.

On this basis, China's relevant research institutes and leading enterprises have not stopped their technological breakthroughs.

In March 2018, Ningbo Institute of materials successfully achieved a breakthrough in the key preparation technology of domestic m60j high strength and high modulus carbon fiber, and the products filled in the blank of domestic market. "After nearly two years of hard work, we have achieved the stable preparation of domestic m60j high strength and high modulus carbon fibers in small batch." The official wechat public account platform of Ningbo materials is disclosed in this way.

In January this year, Ningbo materials realized the stable preparation of high strength and high modulus carbon fiber with tensile modulus of 610gpa in small batch. In order to tackle the key problems of higher-level products, the institute focused on the fiber microstructure design and controllable control, successively broke through the key technologies of controllable molding of high-quality precursor, controllable growth of graphitized microcrystalline structure, design and control of high-efficiency surface structure, and realized the technical breakthrough of CNI qm65 (m65j grade) high-strength and high-mode carbon fiber.

The product has been tested by four domestic professional testing institutions, and the fiber modulus is stable over 630gpa, and the tensile modulus is up to 639gpa.

The test report from Beijing University of chemical technology shows that the tensile strength and modulus of CNI qm65 (m65j) carbon fiber are 3460 MPa and 631 MPa respectively. Its tensile strength is 639mpa from aerospace university.

Next, with the further breakthrough in the field of high strength and high modulus carbon fiber preparation technology by China's relevant scientific research institutes and leading enterprises, as well as the breakthrough of industrialization technology, the independent innovation ability and technical strength of China's carbon fiber industry will be further enhanced, and the competitiveness in the international market will be further enhanced.

A carbon fiber practitioner lamented: "now it seems that with the breakthrough in the field of high strength and high modulus, China's carbon fiber industry will also usher in the stage from" long-term follow-up "to" running with the international. "