In recent years, 3D printing technology has been paid more and more attention. The research on key technologies has made breakthroughs and the performance has been continuously improved. The application in the military field has made important progress and entered the fast lane of development and application. 3D printing will be widely used in the design of weapons and equipment, the manufacture of complex and expensive components, and maintenance support, and will have a positive impact on the development of weapons and equipment.
Compared with traditional manufacturing, 3D printing technology has the advantages of low cost, high speed, good complex manufacturing ability, high material utilization rate and good adaptability in small batch manufacturing. When applied to the development of weapons and equipment, it can significantly shorten the development time of weapons and equipment, reduce the development cost, improve the performance of weapons and equipment, reduce the cost of weapons and equipment, and improve the timeliness and accuracy of maintenance support. With the wide attention and vigorous promotion of all countries in the world, the development and application of 3D printing technology have made breakthroughs in recent years, showing a good military application prospect, which will have a profound impact on the development of weapons and equipment.
1、 Breakthroughs have been made in 3D printing technology and important progress has been made in military applications
In recent years, 3D printing technology has been paid more and more attention. The research on key technologies has made breakthroughs and the performance has been continuously improved. The application in the military field has made important progress and entered the fast lane of development and application.
1. 3D printing technology is increasingly valued and has become the strategic focus of all countries
With the development of rapid prototyping technology, material technology and other key technologies, the application prospect of 3D printing technology has become increasingly prominent and has become the development focus of many countries. The United States listed 3D printing technology as a national key development technology, and gathered the strength of the whole country to develop and seize the development opportunity. In 2012, the United States listed 3D printing technology as one of the 11 key technologies in its plan to restructure the manufacturing industry, and as the main research direction of the first research center of its “national manufacturing innovation network”. The “national manufacturing innovation network” is a product of the “national manufacturing innovation network” program of the United States. It is composed of 15 manufacturing innovation research institutes, mainly studying innovative technologies that play an important role in the development of the manufacturing industry in the United States. China also attaches great importance to 3D printing technology and takes various measures to promote its rapid development. The General Armament Department, the State Administration of science and industry for national defense, the National Natural Science Foundation of China and other departments have supported the laser rapid prototyping of titanium alloy structural parts for many years, and achieved remarkable achievements. The Ministry of science and technology is formulating the development strategy of 3D printing technology, which will further promote its rapid development.
2. 3D printing technology continues to make breakthroughs, and technology maturity and performance continue to improve
In recent years, the research of 3D printing technology has been steadily promoted, and a series of important progress has been made. The technical maturity and performance have been continuously improved. Important progress has been made in the research of 3D printing technology in the United States. The maturity and performance of the technology have been significantly improved, and it has initially reached the industrial application level. In 2012, the new electron beam 3D printing technology of sciaky company of the United States made an important breakthrough, and it has the ability to process large-scale metal parts. The US Department of defense and Lockheed Martin company are preparing to use it to produce high-quality parts of high-value materials such as titanium, tantalum and Inconel alloy for F-35 fighter. All the preliminary tests meet the requirements. 3dsystems has made important progress in laser melting technology. On this basis, the US Air Force will develop 3D printers for printing F-35 fighters and other weapon systems.
The maturity of the space 3D printing technology of the American space manufacturing company has reached level 6, and it has the ability to demonstrate models or prototypes in space. In November 2012, it won the second phase contract of NASA to further improve the technical maturity to level 8, complete the actual system and pass the test and verification, and finally have the ability to be applied to the maintenance, upgrading and life extension of the space station, load upgrading and improvement, hardware space manufacturing and other aspects, In 2014, the first 3D printer was delivered to the international space station. China’s Laser Rapid Prototyping 3D printing technology has reached the world’s leading level. Beijing University of Aeronautics and Astronautics has mastered the technology of using laser rapid prototyping technology to manufacture complex titanium alloy components with an area of more than 12 square meters, and has been successfully applied to the development of weapons and equipment. The related achievement “laser forming technology for large complex integral components of aircraft titanium alloy” won the first prize of the 2012 National Technological Invention Award. Northwestern Polytechnic University has mastered the 3D printing technology of printing titanium aircraft parts more than 5 meters long at a time.
3. The application of 3D printing technology continues to expand and deepen, and the technical benefits continue to play
With the improvement of technology maturity and performance, the application field of 3D printing technology has been continuously expanded in recent years, playing an increasingly important role in the design, manufacturing and maintenance of weapons and equipment. In terms of design, when designing the core components of a new generation of large-scale launch vehicle, NASA uses a large-scale makerbot 3D printer to mold and manufacture the designed components. This 3D printer adopts selective laser melting technology and uses laser to heat and shape metal powder. Compared with NC machine tool manufacturing, it can not only shorten the manufacturing time, but also improve the manufacturing accuracy and reduce the manufacturing cost. In terms of manufacturing, the application of 3D printing technology in the manufacturing of large and complex parts has made continuous breakthroughs.
In 2002, the United States began to install laser formed titanium alloy parts into fighter planes. However, due to the inability to solve technical problems such as deformation and fracture of titanium alloy in the manufacturing process, the United States can only produce small-sized titanium alloy parts and repair the surface of titanium alloy parts [8]. In recent years, the United States has actively carried out research on 3D printing technology to produce large titanium alloy parts. The US military and military enterprises are cooperating with 3D printing technology companies such as 3dsystems and sciaky to promote the application of large-size titanium alloy 3D printing technology in fighter manufacturing.
In 2013, the United States began to use 3D printing technology to mass produce fuel nozzles for jet engines. In terms of the application of 3D printing technology to light material manufacturing, in 2013, the US “solid concept” company successfully manufactured the world’s first 3D printed metal gun, which can continuously launch 50 rounds of bullets and keep them intact. In terms of maintenance, the United States has begun to deploy maintenance support equipment based on 3D printing technology. In July 2012 and January 2013, the US military deployed two mobile expeditionary laboratories for equipment maintenance support. This mobile expeditionary laboratory is a 20 foot long standard container, which can be transported to any place by truck or helicopter. Raw materials such as aluminum, plastic and steel can be processed into required parts using 3D printers and computer digital control equipment.
This can quickly generate needed parts in the battlefield, and even quickly design and produce urgently needed equipment to achieve timely and accurate support. In addition, the U.S. Army has developed a lightweight and inexpensive 3D printer that can be placed in a backpack and used to manufacture replacement parts quickly and cheaply in the battlefield. China has made certain achievements in the application of 3D printing technology in weapons and equipment, and is the only country in the world that has mastered the laser rapid prototyping manufacturing technology of large-scale titanium alloy main bearing components and applied it in engineering. The 3D printing technology of Beijing University of Aeronautics and Astronautics and Northwest University has been successfully applied to the prototype manufacturing of many domestic aviation projects. The main windshield window frame and large central wing root rib of the large passenger plane C919 independently developed by China, as well as the titanium alloy main structure of the new fighter being designed, are all manufactured by laser rapid prototyping technology, which effectively reduces the structural weight of the aircraft, improves the thrust weight ratio of the fighter, and shortens the design time, playing an important role in the rapid development of the new fighter.
In general, the development of 3D printing technology has made important progress. Some fields have reached a high level of technology, and preliminary application results have been achieved, showing good development prospects. However, 3D printing technology is still at the stage of technological development, and there are still problems such as less printable raw materials, low printing accuracy, slow speed and high printing cost, which restrict its further application in weapons and equipment. With the development and progress of material technology, high-precision control technology, efficient manufacturing technology and other key technologies, 3D printing technology will play a greater role in the development of weapons and equipment.
2、 The application of 3D printing technology in the military field will have a profound impact on the development of weapons and equipment
Limited by technology and cost, 3D printing technology is difficult to replace large-scale assembly line production. However, it does not require molds, and can realize direct conversion from design to parts and complete rapid and free manufacturing. It will be widely used in the design of weapons and equipment, the manufacture of complex and expensive components, and maintenance support, and will have a positive impact on the development of weapons and equipment.
1. Small batch manufacturing has low cost and high speed, which can significantly reduce the risk of weapon equipment development and shorten the development time
Weapons and equipment are becoming more and more complex. Only through multiple rounds of design – prototype production – Test – modified design – prototype reproduction – retest can problems be found and corrected in time. However, the production of prototypes is very small, and the traditional manufacturing method takes a long time and costs high, resulting in a long period of weapon equipment development and high costs. Because of repeated experiments and manufacturing in the development process of the F-35 fighter, the development time has been prolonged for many times, and the development cost has increased significantly.
3D printing technology does not need the ingot, embryo, mold, die forging and other processes of traditional manufacturing methods. It can carry out prototype production quickly and at low cost, and the whole production process is digitized. It can be modified and manufactured at any time, and a large number of verification tests can be carried out in a short time, so as to significantly reduce the development risk, shorten the development time and reduce the development cost. In the design of the curiosity Rover and the new generation large-scale launch vehicle, NASA has adopted 3D printing technology for rapid manufacturing of parts. The key parts of the landing gear of the new fighter in China are also manufactured by laser rapid prototyping technology, which greatly shortens the development cycle.
2. The complex manufacturing capability is good, which can complete the manufacturing difficult to be completed by traditional methods, and improve the performance of weapons and equipment
3D printing technology does not need to make a model in advance. It is truly free manufacturing and can form almost any shape of parts. It is particularly effective for parts with complex internal structures. Such as manufacturing complex titanium alloy structural parts, Aero-engine Turbine Blades with complex internal cooling channels, tank armor and other key weapon parts with complex internal materials and structures. 3D printing technology can also significantly improve the key performance of parts.
The parts manufactured by laser sintering technology have properties that exceed or equal to those of forgings, especially high temperature, endurance and fatigue resistance. For example, the ultra-high strength steel for aircraft landing gear manufactured by selective laser sintering technology has a fatigue strength 20% higher than that of forgings, and the 900 degree fatigue strength of turbine blades manufactured can be 40% higher than that of the second generation single crystal. In addition, 3D printing technology can also be used for local composition control to produce functional gradient materials with controllable local material properties (such as refractive index, conductivity, magnetism, hardness, etc.), so that the materials show some special properties. DARPA is funding the research of printing gradient index lens (quartz) with 3D printer, which can be used to develop optical stealth cloak.
3. High material utilization rate, which can effectively reduce the production cost of advanced weapons
The traditional manufacturing is “reduced material manufacturing”. By cutting, extruding and other operations on the raw material blank, the redundant raw materials are removed and the required part shape is processed. The raw materials removed in the processing process are difficult to be recycled, and the waste of raw materials is serious. For example, the weight of the largest titanium alloy integral reinforcing frame part in the U.S. F-22 fighter is less than 144Kg, while the weight of the blank die forging is 2796kg, and the utilization rate of titanium alloy material is less than 5.2%. The massive waste of expensive materials directly increases the cost of weapons and equipment, making it increasingly difficult for weapons and equipment to bear. The cost of the US F-22 fighter is more than US $200 million, which is difficult for even an economic power like the United States to bear. 3D printing only adds raw materials where needed, and the material utilization rate is extremely high. It can make full use of expensive raw materials and significantly reduce the cost of weapons and equipment. If the laser forming technology is adopted, the weight of the finished blank of the central wing root rib of C919 aircraft is only 136 kg, which can save 91.5% of the expensive titanium alloy material compared with the 1607 kg forging blank of the traditional manufacturing method.
4. It has the ability to rapidly manufacture different parts and components, which can effectively improve the real-time and accuracy of weapon and equipment maintenance support
At present, equipment maintenance support mainly adopts the method of redundant backup, that is, a large number of parts are prepared in advance and replaced when the equipment is damaged. As the damage of equipment is difficult to predict, this method is prone to two situations of insufficient support and excessive support. In case of insufficient support, the timely repair of weapons and equipment will be affected due to the lack of spare parts prepared in advance. In case of excessive support, the support pressure will be increased due to the excessive spare parts prepared in advance. 3D printing technology has the ability to rapidly manufacture different parts. As long as there are electronic design drawings and printing materials, various parts can be quickly printed as required. When applied to maintenance support, it can quickly print out damaged parts in the battlefield, timely and accurately complete the maintenance support of damaged equipment, and quickly recover the combat capability. Recognizing the great potential role of 3D printing technology in improving equipment maintenance support, the United States actively explored the application of 3D printing technology in equipment maintenance support. In 2012 and 2013, it deployed two mobile expeditionary laboratories based on 3D printing technology to verify equipment maintenance support based on 3D printing technology.
Accelerating the development and application of 3D printing technology is an effective way to make up for the deficiency of our current weapon equipment design, manufacturing and maintenance support capability, improve the research and development efficiency, reduce the manufacturing cost, and improve the timeliness and accuracy of maintenance support. China’s 3D printing technology is in the leading position in the world in the laser forming of large and complex integral components of titanium alloy, but the overall level still has great room for improvement. We should focus on the long-term development of weapons and equipment, make overall planning, gather forces from all sides to promote the development and application of 3D printing technology, and provide technical support for achieving the goal of “being able to fight and win”.
First, take 3D printing technology as the key to the upgrading of China’s manufacturing industry, integrate military and civilian resources, and gather the strength of the whole country for development;
Second, in view of the current problems, strengthen the research on the core and key technologies of 3D printing of material technology, and change the situation that the core and key equipment in China are controlled by others;
Third, actively explore the application of 3D printing technology in the construction of weapons and equipment, and use the application to guide the development direction and focus of technology.