Welcome! Visit Vietnam Shengge enterprise official websiteChinese / English / Vietnam
     
Current location: home page>>news
Application prospects of global 3D printing technology in aviation industry
发布者:     来源:   时间:2016-11-25  

3D printing technology began to appear in the late 70s of last century. It was mainly used in the rapid prototyping and production stage of the product development stage". 3D printing technology is similar with the surfacing method have been used in industrial production, it is called 3D printing, is the use of 3D CAD data model and computer in the molding process, the two dimensional substrates through different fusion methods combined into three-dimensional structure. The methods used in aviation production include laser near net forming technology (LENS), laser selective melting (SLM) and electron beam selective melting (EBSM).
3D printing complex reduction effect of frame structure in blank is quite obvious, such as the F-22 largest forging structure of blank box weighs 2790 kg net weight of only 144 kg after rough machining, material removal ratio reached 95%! The forging process can not be directly made into the detail structure, if the manufacturing process has been verified according to the process requirements that have been verified. The material utilization ratio is only about 10% of the blank weight. Casting can complete some of the details of the rough molding, blank actual utilization rate can reach 20%~25% of the total weight. 3D printing can be directly made and finished to shape, taking into account the appearance of materials and processing technology of quality requirements, the finished parts can achieve the blank weight 60%~70%, material utilization rate and machining efficiency are greatly improved.
In contrast, the casting mold reuse effect is better, the finished core type can be batch blank manufacturing. Forging forging die cost is high, the process equipment standards are also high, but the forging is also conducive to batch production of rough molding. 3D printing process used by means of material manufacturing, it only made 1 or 100 batch manufacturing, there are no differences in single production time and cost, and quality control requirements of parts of the molding process is more strictly.
Comparison of 3D printing with other blank making methods
Aviation applications 3D printing technology at this stage is mainly concentrated in the metal structure, titanium alloy and alloy steel billet molding difficult, low processing difficulty of aluminum is more suitable for casting molding. 3D printing of aviation parts has been widely used. For foreign 3D forming TC4 joint F-22 has reached 2 times the design fatigue life and structural strength of root hanger to meet the design requirements of the F/A-18 225%, the fatigue life is up to 4 times the design requirements, C-17 and other types of accessories have inlet volume applications 3D printing, 3D printing parts have been able to replace existing in sheet metal and casting aircraft.
Chinese made great achievements in aviation 3D printing, there are a number of types of application of 3D printing bearing structure, to shorten the manufacturing cycle and simplify the process effect on product weight loss effects are more obvious, promotional materials and even had lost 40% argument. Many military fans in China, based on the 40% and similar statements, have great hopes for the weight reduction of the aircraft structure, and this 40%, although theoretically possible, is subject to very strict conditions and application restrictions.
The precision of SLM products is higher, but the control effect of molding structure density is not good, it is difficult to withstand the structural effect of high load. The 3D printing of bearing structure mainly adopts LENS. According to the published 3D print the whole frame of billet shape comparison, blank weight 3D print roughly only 15% this is forging, 3D printing technology advantage, but the billet weight than the weight does not mean the end of manufactured goods. The design of the overall framework of the aircraft to take into account the lightweight, strong consistency, physicochemical properties and mechanical / technology and product structure design, must strictly meet the standard requirements of different models, the design of similar structures and there is no big difference.
There is no difference between the structural design and the forging frame of the 3D printing bearing frame, which is open in the exhibition. The difference is only reflected in the molding process of the roughcast. LENS and SLM are 3D printing technology has been relatively mature, whether using laser or electron beam as an energy source, whether it is the use of wire or powder material as the substrate, the physical and chemical conditions of the material itself and not because of different processing methods and changes. According to the existing technology, the theory of material density and near net shaping sintering nearly 1% less than forging, powder molding material density selective melting mode is relatively small, and the density difference of forging is below 3%. The process conditions for the realization of the better material density difference is smaller.
No matter what kind of 3D molding is adopted, the material properties of the same part will not be significantly different if there is no big difference in the weight of the finished product. So, the effect of weight loss achieved 3D print blank processing method is very limited, considering the material properties of 3D printing is still not perfect, compared with the mature forging structure of tolerance design more insurance, the same net structure design even heavier.
According to the published data, the finished product of 3D printing parts of titanium alloy, the tensile strength and hardness of forgings has reached the standard, but the fatigue life and crack tolerance by process influence, the future time is not fully substitute for forging conditions. A large number of integrated forging frames used in American aircraft manufacturing are not active enough for high-risk 3D printing, which takes into account the difficulties in product life and quality control. While applying the 3D printing force structure in the new machine manufacturing, China has also invested a great deal of money and technical force in developing large-scale forging machines, and it is also unable to solve the batch production requirements of large finished products because of 3D printing. 3D printing and forging / casting each have advantages, as long as the aviation


Edition@Copyrights 2013-2030  www.sginternational.vn    Copyright: Viet Nam Da Ge Machinery Co., Ltd.