Recently, the National Science and Technology Awards Office of China announced the list of acceptance projects for the 2020 National Science and Technology Awards. Among them, "micro-casting and forging synchronous ultra-short process manufacturing technology and equipment for large and complex high-end parts", namely metal 3D printing "micro-casting and forging" Nominated the first prize of the 2020 National Technology Invention Award. The nomination opinion described, "This major original achievement strongly supports the independent innovation of high-end equipment in China, leading the revolution in short-process manufacturing technology and the green transformation and upgrading of traditional industries.
It was jointly developed by Huazhong University of Science and Technology and WHTY Intelligent Manufacturing Co., Ltd. The joint team creatively combined metal casting and forging technology into one, pioneered the method and theory of simultaneous manufacturing of micro-casting and forging materials, invented and developed a group of independent knowledge The micro-casting and forging simultaneous manufacturing technology and equipment of property rights and core competitiveness have overcome the problem of "stuck neck" which cannot be manufactured by large-scale complex high-end forgings with high quality and short process. The expert group believes that this original metal 3D printing technology can nominate the first prize of the national technological invention, which fully shows that the technology has great advantages in originality, leading edge, technical difficulty and mature completeness, as well as huge social benefits and development prospects and potential.
At the production base of metal 3D printing "micro-casting and forging" equipment, the reporter saw at the scene that one by one complex metal parts combined with a unique micro-casting and forging-milling process, while printing and processing, appeared as stunning works of art on the production line. "We collect light, electricity, heat, force, sound and other comprehensive signal data online, and use self-written algorithm modeling and analysis to conduct stability monitoring and defect judgment to achieve simultaneous casting and forging, synchronization of casting and forging, and shape control. In order to ensure the high reliability and stability of additive manufacturing forgings, "Wang Haiping, a doctoral student of the Zhang Haiou team, said," The integrated manufacturing process of casting, forging and milling must be extremely rigorous. There must be no loss of influence on the casting and forging properties! "
"Traditional craft casting, forging, and milling are carried out separately, but integration is achieved on this machine." Zhang Haiou explained that if you want to make a precision and complex part as dumplings, you need to make dough and roll. If one of the links is not in place, the filling may be exposed after the bottom of the pot. Now these processes are combined together, and the filling is tightly combined, so the filling will not be exposed. "The stuffed dumplings can still be eaten, but the parts" stuffed stuffing "will be loose and can only be scrapped."
It is often said that good steel must be "hardened" and "forged", because only repeated forging can increase the strength, toughness and fatigue life of the cast metal to the level of forgings. Modern manufacturing is to manufacture high-end metal parts by first casting, then forging, and then milling, but this method has the disadvantages of long process flow, huge energy consumption for repeated heating, heavy pollution, and can not produce multi-functional parts with material changes. For example, the overall turbine of an aero engine.
Conventional metal 3D printing technology also has fatal flaws: first, without forging, the comprehensive mechanical properties are not as good as forgings, especially toughness and fatigue performance; second, the metallurgical quality is difficult to control, and it is easy to produce metallurgical defects such as porosity and unfusion; third, equipment cost And the manufacturing cost is high. The heat source mostly uses high-power laser or electron beam, which needs the whole sealed protection, the forming space is limited, and the material cost is expensive.
In 2015, the team of Zhang Haiou developed micro-casting and forging synchronous composite equipment, and printed the world's first batch of forgings: railway key frogs and transitional forging of important parts of aero engines. Experts said that this new method of manufacturing parts is "high-efficiency, short process and low-cost green intelligent manufacturing."
Since the resumption of work, the 3D printing "micro-casting and forging" industrialization team has received the first order in the field of nuclear power, and the research team is also stepping up research and development of new high-end parts involving aerospace, ships and other fields, including aluminum alloy cabins, stainless steel pump push Impeller, bottom beam of ultra-high-strength steel hanging box section, and titanium alloy hanging outer rear joint, etc. "Although the epidemic caused us to press the pause button for a few months, our scientific research work has not stopped for a moment. Now that all the staff have resumed work, we have increased our horsepower production. The annual production capacity can reach about 50 million. "Zhang Haiou said.
At present, the products manufactured by this technology have been applied to the equipment manufacturing fields of heavy aircraft such as large aircrafts, aero engines, gas turbines, aerospace, ships, advanced rail transit, nuclear power, etc.
About WHTY Intelligent Manufacturing Co., Ltd.
WHTY Intelligent Manufacturing Co., Ltd. is a company based on metal 3D printing, metal parts repair and remanufacturing, industrial intelligent systems, etc.
At present, the company owns intelligent factories of 8,000㎡ and advanced production lines, mostly used for the engine, aerospace, shipbuilding, nuclear power industry, weapons and equipment, marine industry, petrochemical, high-speed rail, automotive, metallurgy, environmental protection and other high-end areas. Its meteoric rise in 3D printing field has made it one of the most creative enterprises in China.
The company's R & D team, leading international progress in research and development, consists of leading figures from prestigious universities at home and abroad, well-known experts, as well as well-educated multi-level young talents. In recent years, the company's R & D team invented the "intelligent micro-casting and forging milling composite manufacturing (3D printing)" technology that integrates casting and forging as one process. It solved global problems in 3D printing technology, making China a leading character in the field and the company an international enterprise for the first time.