Laser Welding Development Process

The world's first laser beam was produced in 1960 by using a flash bulb to excite ruby ​​crystals. Due to the heat capacity of the crystal, it can only produce a very short pulse beam with a very low frequency. Although the instantaneous pulse peak energy can reach 10^6 watts, it is still a low-energy output.
Using neodymium (ND) as the excitation element, yttrium aluminum garnet crystal rod (Nd:YAG) can produce a continuous single-wavelength beam of 1-8KW. YAG laser, with a wavelength of 1.06uM, can be connected to the laser processing head through a flexible optical fiber. The equipment layout is flexible and suitable for welding thickness of 0.5-6mm.
Using CO2 as the excitation material, CO2 laser (wavelength 10.6uM), the output energy can reach 25KW, and a single-pass full penetration welding of 2mm thick plate can be made. The industry has been widely used in metal processing.
In the mid-1980s, laser welding as a new technology received widespread attention in Europe, the United States, and Japan. In 1985, Germany's Thyssen Steel Company cooperated with Volkswagen AG to successfully use the world's first laser-welded plate on the Audi 100 body. In the 1990s, major automobile manufacturers in Europe, North America, and Japan began to use laser-welded plate technology on a large scale in car body manufacturing. Practical experience in both laboratories and automobile manufacturers has proved that welded plates can be successfully used in the manufacture of automobile bodies.
Laser welding uses laser energy to automatically splice and weld several steels, stainless steels, aluminum alloys, etc. of different materials, thicknesses, and coatings to form an integral plate, profile, sandwich panel, etc., in order to meet the different requirements of parts for material properties, and to achieve lightweight equipment with the lightest weight, optimal structure, and best performance. In developed countries such as Europe and the United States, laser welding is not only used in the transportation equipment manufacturing industry, but also in the construction industry, bridges, home appliance plate welding production, rolling line steel plate welding (steel plate connection in continuous rolling), etc. It is widely used. World-renowned laser welding companies include Soudonic of Switzerland, Arcelor Steel Group of France, TWB of ThyssenKrupp Group of Germany, Servo-Robot of Canada, Precitec of Germany, etc.
The application of laser welded plate technology in China has just started. On October 25, 2002, China's first specialized commercial production line of laser welded plate was officially put into operation, which was introduced by Wuhan ThyssenKrupp Zhongren Laser Welding from TWB of ThyssenKrupp Group of Germany. Since then, Shanghai Baosteel Arcelor Laser Welding Company and FAW Baoyou Laser Welding Co., Ltd. have successively put into production.
In 2003, foreign countries realized double-beam C02 laser wire welding and YAG laser wire welding of A318 aluminum alloy lower wall panel structure, which replaced the traditional riveting structure to reduce the weight of the aircraft fuselage by 20%, and also saved 20% of the cost. Gong Shuili believes that laser welding technology will have great significance for the transformation and upgrading of my country's traditional aviation manufacturing industry. Afterwards, he immediately applied for a number of related pre-research projects, organized a research team, and took the lead in introducing the "dual-beam laser welding" technology into the research project in China, and from the beginning, he planned to use this technology in aircraft manufacturing. The Chinese expert team explained the preliminary technology to a certain aircraft design institute and introduced the superiority and feasibility of dual-beam laser welding to them. After multiple verifications and evaluations, the design institute resolutely decided to use this technology for the manufacture of a certain aircraft with ribbed wall panels, achieving the initial goal of applying the "dual-beam laser welding" technology to aircraft manufacturing, breaking through key technologies such as light alloy laser welding wire filling precision control, integrating and innovating the development of dual-beam laser wire filling composite welding equipment, and establishing the first domestic high-power dual-beam laser wire filling welding platform, realizing dual-beam double-sided synchronous welding of large thin-walled structure T-joints, and successfully applied it for the first time in the welding and manufacturing of key structural parts of aviation ribbed wall panels, playing an important role in the development of new aircraft in my country.
In 2003, the first large-scale strip online welding equipment provided by HGLASER passed the offline acceptance. This equipment integrates laser cutting, welding and heat treatment, making my country's HGLASER the fourth company in the world that can produce such equipment.
In 2004, HGLASER Farile's "High-power laser cutting, welding and cutting and welding combined processing technology and equipment" project won the second prize of the National Science and Technology Progress Award, becoming the only laser company in China with the ability to develop this technology and equipment.
With the rapid development of the industrial laser industry, the market has higher and higher requirements for laser processing technology. Laser technology has gradually shifted from a single application to a diversified application. Laser processing is no longer a single cutting or welding. The market has more and more demands for laser processing to integrate cutting and welding. Laser processing equipment integrating laser cutting and laser welding has come into being.
HGLASER Farile has researched and developed the Walc9030 cutting and welding machine, which is a super large format of 9×3 meters and is currently the world's largest integrated laser cutting and welding equipment. Walc9030 is a large-format cutting and welding equipment that integrates laser cutting and laser welding functions. The equipment has a professional cutting head and welding head. The two processing heads share a beam. CNC technology is used to ensure that they will not interfere with each other. The equipment can complete two processes that require cutting and welding at the same time. Cut first and then weld, weld first and then cut, laser cutting and welding can be easily switched. One device has two functions without the need to purchase new equipment. It saves equipment costs for application manufacturers, improves processing efficiency and processing range, and because of the integration of cutting and welding, the processing accuracy is fully guaranteed, and the equipment performance is efficient and stable. In addition, it overcomes the difficulties of thermal deformation of the plates during the welding process of super-large plates and how to maintain the stability of the super-long flight optical path. Two flat plates with a length of 6 meters and a width of 1.5 meters can be welded at one time. The surface is smooth and flat after welding, and no other subsequent processing is required. At the same time, it can cut plates with a width of more than 3 meters and a length of 6 meters and less than 20mm, forming them in one time without the need for secondary positions.
The Shenyang Institute of Automation of the Chinese Academy of Sciences has carried out international cooperation with Ishikawajima-Harima Heavy Industries, Ltd. of Japan. Following the national scientific and technological development strategy of introducing, digesting and then innovating, the Institute has conquered several key technologies of laser welding and developed the first complete set of laser welding production lines in China in September 2006. It has also successfully developed a robot laser welding system, which has realized laser welding of planes and space curves.
In October 2013, Chinese welding experts won the highest academic award in the field of welding - the Brooke Award. The Welding Institute (TWI) of the United Kingdom recommends nominations from more than 4,000 member units from more than 120 countries every year, and finally awards the award to an expert in recognition of his outstanding contributions to welding or connection science and technology and industrial applications. This award is not only a recognition of Gong Shuili and his team, but also an affirmation of AVIC's efforts to promote the advancement of material connection technology.