Magnesium is the lightest useful metal material in the world and plays an important role in the defense industry, aerospace, transportation and other fields. At the same time, magnesium is also the metal material with the highest hydrogen storage density available, with significant advantages in innovative applications in energy, medicine and agriculture.
The national university Huang Danian-style teacher team-the "Light Hydrogen Magnesium" research team led by Ding Wenjiang, an academician of the Chinese Academy of Engineering, has overcome the three major bottlenecks of low strength, thermal tolerance and short life of magnesium alloys, making magnesium an important weapon in my country's new generation of "big countries." "Played an irreplaceable role in the development plan. Ding Wenjiang's team also conquered the low-cost batch preparation technology of magnesium-based hydrogen storage materials, developed the world's leading solid-state hydrogen storage technology, and achieved a hydrogen storage density equivalent to that of liquid hydrogen at room temperature and pressure, making hydrogen energy both high-energy Density and high safety; making it possible for magnesium materials to make "hydrogen medicine" for the first time, magnesium hydrogen materials have broad application prospects in the fields of medicine and agriculture. The research results of Ding Wenjiang's team have brought Chinese magnesium to the world, and it has come to the forefront of the world.
Recently, at the 24th China Association for Science and Technology Annual Meeting, jointly organized by the Advanced Materials Society of the China Association for Science and Technology, the Hunan Science and Technology Association, the Hunan Provincial Department of Industry and Information Technology, the Hunan Provincial Department of Science and Technology, and the Changsha Municipal People's Government. At the special event - "International Forum on Innovation and Development of New Materials Industry", Academician Ding Wenjiang, academician of the Chinese Academy of Engineering, made a keynote speech entitled "Innovative Cultivation of Magnesium with Light Hydrogen", "I have been studying magnesium for 38 years. During these 38 years I mainly do two things: one is to study the lightweight of magnesium, and the other is to study magnesium in hydrogen science because one magnesium atom can carry two hydrogen atoms.”
According to Ding Wenjiang, my country's magnesium reserves are very rich, accounting for about 90% of the world's total. Magnesium has several advantages: first, it is very light, its density is only 1/3 of aluminum and 1/4 of steel; second, magnesium has a high damping coefficient, and the shock absorption performance is very good; third, it has good biocompatibility, The density of magnesium alloys is usually 1.74-2.0g/cm3, which is similar to the natural bone density of 1.8-2.1g/cm3, and has good biomechanical compatibility; Fourth, it is more environmentally friendly, and magnesium alloys can be simply recycled without reducing its performance. Mechanical properties, and the energy consumed during regeneration and melting only accounts for 4% of the energy consumed in the manufacture of new materials.
"Therefore, magnesium is an important material in aerospace, transportation, electronic information, energy power, biomedicine and other fields. In the military mouth, magnesium is mainly used for military equipment or weapon manufacturing. Because magnesium emits light at high temperature, It can also be used for firecrackers or flares; in Minkou, magnesium is one of the non-ferrous metals widely used in automobiles, IT products, and medical aids." Ding Wenjiang further introduced, "Although high-speed rail is already a business card in my country, high-speed rail The materials used on the high-speed rail still need to be further developed and innovated. Many parts on the high-speed rail can be made of lightweight magnesium, of course, its stability and corrosion resistance must also be considered. This will be a 100 billion yuan level. According to the forecast of the Korea Magnesium Industry Technology Research Association, the global magnesium metal market will increase by 7.1% annually, and will reach a scale of 620 million US dollars in 2026.
"Recently, the application expansion of magnesium in national defense is also particularly strong. If you want to create weapons and equipment that can hit farther, fly faster, and have a longer life, the requirements for lightweight materials are very high. For example, near space hypersonic speed For aircraft, the use of magnesium in the wing frame can achieve a comprehensive weight reduction of 100 kg, and the range will increase by 8%, which is greater than 1400 kilometers; for example, the Eagle Strike hypersonic anti-ship missile, the cabin has also begun to use magnesium, which is the first time in the world to use magnesium Let's do it." Ding Wenjiang said that in the civilian field, the focus has recently been on the wheels of heavy-duty trucks. If magnesium wheels are used to replace aluminum wheels, the energy can reach at least 10%; there is also a fuel vehicle engine block, which is also very important for light weight; and magnesium alloy automotive chassis components, which can be further considered in new energy vehicles. For one, the weight can be reduced by 52% after integrated die casting.
The industrial application of magnesium alloy materials has become a research hotspot in the field of metal materials in recent years. With the vigorous promotion and use of new energy vehicles, the construction of high-speed rail, the accelerated breakthrough in aerospace, and the rapid development of 5G networks, magnesium alloys will be in the next few years. The research and development and application will usher in greater opportunities and market prospects. In the future, the research and development of high-end ultra-high-performance magnesium alloy materials and the improvement of the precision machining capabilities of high-performance and low-cost magnesium alloy complex parts will be important development directions, thereby boosting the development of lightweight equipment, and the development of magnesium alloy materials for national major projects. The localization rate will also approach 100%.
"Magnesium of Hydrogen Science"
Ding Wenjiang pointed out in the report that magnesium has three major applications in the field of hydrogen energy.
"One is the lightweight of magnesium materials and new energy vehicles. The specific gravity of magnesium is very light, only 1.74, which is similar to plastic. One magnesium atom can carry two hydrogen atoms, which can solidify hydrogen in a relationship with hydrogen, and hydrogen can be cured under certain conditions. It can also come out under certain conditions. Moreover, after the catalyzed water is released, the hydrogen in the water can also be taken out. In this way, the hydrogen storage capacity is very considerable. Magnesium materials are lighter in weight than aluminum. Structural parts, magnesium alloy structural parts can achieve a 30% weight reduction effect. In addition, the strength, service life and other performance indicators are not inferior to aluminum alloys." Ding Wenjiang's team achieved controllable through the innovation of the preparation process. The company's hydrogen desorption technology, "making hydrogen in and out of magnesium very convenient", has also prepared a series of industrial production equipment for different application scenarios.
"The second is the integration of magnesium materials and hydrogen purification, storage and transportation. For solid-state hydrogen storage of magnesium, the hydrogen input may not be very clean, but the purity of the released hydrogen can reach 99.999%. Therefore, it is called the integration of purification, storage and transportation. Cost On the other hand, compared with the current stadium trailers to transport hydrogen, the integrated cost of magnesium purification, storage and transportation can be reduced by about 40%, and it is not affected by the distance of storage and transportation, and has inherent advantages in magnesium-based solid-state hydrogen storage. Magnesium-hydrogen solid-state hydrogen storage tanks can be placed directly on the large truck. 15~20 such products are placed on the large truck, and a single vehicle can load 1.2 tons of hydrogen, and it is transported at normal temperature and pressure, without any danger Whether it is a car, train, container, or safe transportation at normal temperature and pressure, it can be realized. The current preliminary assumption of the application scenario of this product is that directly putting down two container vehicles for storing and transporting 2.4 tons of hydrogen is equivalent to a hydrogen refueling. After 12 years of research and development, Ding Wenjiang's team has formed a large-scale production technology of 30 tons, which can be produced in batches at low cost, and the output is internationally leading. "Britain, Japan and some advanced western countries want to do some experiments, and they will all come to us to order." Ding Wenjiang said.
"The third is magnesium material and hydrogen energy power system. Generally, the self-control time of drones will not exceed half an hour. Using high-energy, high-density magnesium hydride fuel cell systems for drones can make drones fly in the air. Continue to fly for 10 hours, with an average of 55 kilometers per hour, and the continuous range can reach 500 kilometers. Realize the safety of drones in cities, forest fire prevention, and high-voltage power lines.
Domain inspection. "
In addition, Ding Wenjiang also mentioned the related research on hydrogen fuel cells for new energy vehicles that the team has been deploying in recent years: "A membrane electrode, a bipolar plate, these two are the core components. We developed a magnesium alloy. The bipolar plate can be soaked in hydrofluoric acid for three months without any problem, the corrosion resistance is very strong, and the specific gravity is very light, so it has great application potential.”
Magnesium is degradable in the human body, avoiding the secondary surgery, secondary infection and extra cost required by other commonly used biomaterials. At the same time, as a stent material for cardiovascular, it can effectively reduce the negative remodeling of diseased blood vessels, vascular restenosis and intimal hyperplasia. Ding Wenjiang said: "Magnesium alloys can be used as biological materials. In terms of importance, the second most important mineral in the human body is magnesium. Magnesium is responsible for important energy transmission functions in cells, and it helps the cell membrane to regulate the appropriate amount. The need for calcium promotes the normalization of physiological functions. Many medical diseases are directly related to magnesium deficiency. Magnesium is an element that is very beneficial to the human body. Japan, the United States, and Europe now have magnesium supplements. "At present, biological magnesium Alloys are mainly used in the preparation of bone repair implants and tissue engineering scaffolds such as cardiovascular scaffolds.
"With regard to cardiovascular stents, the currently clinically used medical metal materials mainly include stainless steel, cobalt-based alloys, and titanium alloys. Such stents will remain permanently in the human body and cannot be degraded, requiring patients to take anti-rejection drugs for a long time. Moreover, it is easy to re-block in the stent, requiring a second operation, which is very risky. If magnesium materials are used and controlled degradation is carried out, this problem can be well solved.”
Speaking of magnesium alloys as bone fixation materials, Ding Wenjiang said: "At present, the biomedical materials widely used in bone plates and bone nails are mainly titanium, titanium alloys, stainless steel, etc., but they all have certain limitations. After being implanted into the human body, because the elastic modulus of the human bone material does not match, the force of the human bone will be blocked. In addition, these materials are not degradable in the human body. When the patient's bone grows and heals, it needs to be removed through a second operation. Ding Wenjiang further introduced, "Magnesium alloy bone fixation material is more compatible with the mechanical properties of human bone, which can effectively avoid the stress shielding effect. After the human bone is basically healed, the magnesium alloy will be degraded into non-toxic and harmless small molecules, which are passed through the human body. The circulatory system is expelled from the body, which avoids the pain of removing the steel nail and the steel plate in the second operation of the patient, and also saves the operation cost.”
Ding Wenjiang further mentioned, "For example, during the replantation of a severed hand, a nerve wire is needed. If a titanium wire is used, it will remain in the nerve forever because it cannot be degraded by corrosion in the human body. Magnesium wire, when the nerve wire grows, the magnesium wire can disappear through degradation."
Finally, he emphasized that effective scientific research must be done to be able to innovate and make technological prototypes. "If there is neither originality nor effect, but only imitation and copying, this is ineffective scientific research that wastes human, material and financial resources," Ding Wenjiang said, "When we engage in materials science and engineering, we must make the best use of materials, and the forming process must be flexible. For." The 16-character policy of "to be good at materials, materials to become materials, materials to be made into tools, and tools to be easy to use" has always been the research and development concept followed by Ding Wenjiang's team, "In researching new materials, materials science and materials engineering cannot be combined To separate, we must combine materials and technology. Especially in the field of engineering, we should pay more attention to the needs of the country and the development of people's livelihood, closely integrate academic research with the development of productivity, and seek greater development space. After 40 years of innovative cultivation, magnesium' will have great potential in defense and military industry, transportation, biomedicine, energy environment, green agriculture and more unknown fields in the future, let us wait and see." Ding Wenjiang is full of hope.