Musk wants to use a lower cost, the car to do like a mobile phone FMCG, the best broken direct replacement, originally only need tens of thousands of maintenance costs, after using Tesla integrated die casting technology directly rose to 200,000, this technology is cutting leeks or real subversion? Is such an electric car acceptable? If it is really subversive, then Tesla has registered an exclusive patent for heat-free materials, will China be subject to people?
Many people mistakenly think that the die casting technology is Tesla made, in fact, Ford has adopted die casting technology as early as F150, but the die casting in Ford's hands is not fire, and Tesla is directly popular in the world, which reflects Musk's strong appeal, really not convinced. After that, Tesla used a large die casting machine to complete the replacement of the "stamping + hundreds of robot welding" link, replacing a large number of small parts with a single large aluminum casting, which not only improved the endurance of electric vehicles, reduced costs, improved production capacity, but also promoted the transformation of the automobile body manufacturing process.
How can domestic manufacturers not follow up in the face of the huge competitiveness brought by integrated die casting technology? In order to improve the endurance, Weilai Automobile uses an all-aluminum body, of which 30% is an aluminum casting, but because it does not use a larger die-casting process, it has to use a complex connection process to create a body-in-white, which includes 7 kinds of complex processes such as hot-melt self-tapping riveting, self-punching riveting, aluminum spot welding, etc. The trouble is to die, so in order to increase production capacity and reduce costs, Weilai's willingness to follow up is very resolute.
Including the cooperation between Gaohe Automobile and Tuopu Group, it has successfully mass-produced the first integrated super-large die-cast rear cabin in China. This is currently the largest known integrated aluminum alloy die casting in the field of auto parts, achieving a weight reduction effect of 15%-20%. So the question is, domestic manufacturers do have the ability to make integrated die castings, but how is the technical level compared to Tesla?
Traditional aluminum alloy die castings need to be solid solution and heat treatment to meet the strength and toughness required for body performance. The integrated die-cast body structural parts, large in size and small in wall thickness, simply cannot withstand the deformation caused by heat treatment, especially in the case of such a large size as the body, even a small deformation will not be able to stand, because this thing will be installed and matched with other parts of the body after it is made, so the requirements for accuracy are very high. Some people say that the deformation can be forcibly adjusted by orthopedic, but this will cause some losses on the parts, and the final result is that the pass rate is very low, and the cost will be very high.
Therefore, at this time, it is necessary to develop a heat-free aluminum alloy material, which does not need to be heat treated after die casting to meet the mechanical properties required by the body structure. It can be heard from the name that this material can be used to achieve die casting, and the performance of all aspects of strength can meet the requirements. Most of the aluminum alloy materials, such as the German Rheinland aluminum industry that we use more, this is the leader in the field of casting aluminum alloys, most of the casting aluminum alloy materials at home and abroad, are from Rheinland Aluminum, and everyone has made various changes and improvements on the basis of it. Tesla poached aluminum alloy expert Charles Coyman from Apple in 2015 to develop this heat-free aluminum alloy material. The exclusive patented aluminum alloy material is the core barrier of Tesla's integrated die-casting technology.
In addition to Tesla's registered patent "die-cast aluminum alloy for structural components", Huaren Express and Shanghai Jiaotong University have also successfully developed a low-carbon aluminum alloy material for TechCast super castings, which has a fluidity of more than 15% higher than that of the same level of materials and more than 30% of the strong plastic product, reaching the international leading level. NIO has also successfully verified the application of EZCAST series high-strength cast aluminum alloys on large structural parts. Including Lizhong Group, it has also developed heat-free aluminum alloy materials, and obtained the invention patent authorization in 2020, which is the only enterprise in China that has obtained the patent certificate of the material, and has now achieved mass production.
From the process point of view to analyze, integrated die casting essentially belongs to the high-pressure casting process, vacuum high-pressure casting production of aluminum body structural parts, higher strength, better quality, so is the current main technical route. Domestic Wencan shares believe that everyone is very familiar, in 2015 into the Tesla supply chain, the current supply of aluminum alloy high-pressure casting body structural parts to Tesla, Weilai, Mercedes-Benz, the comprehensive ability is relatively strong, die casting machine mold can do their own, heat-free treatment material technology has also been mastered, is the earliest research and use of vacuum high-pressure casting process to produce aluminum alloy enterprises, but also the domestic large-scale mass production of aluminum alloy body structural parts of the leader, the product basically covers all aluminum alloy body structural parts. At present, it has realized large-scale, complex, thin-walled integration and lightweight manufacturing, and is 4-5 years ahead of domestic counterparts in technology. A few days ago, Wencan also completed the trial production of ultra-large integrated aluminum alloy back floor products, supplying new forces to car manufacturers, which were die-cast by 9,000 tons die casting machine.
Therefore, we have accumulated technology, including Xiaopeng Wuhan factory, and have also joined the integrated die-casting process workshop, which is not a monopoly technology of Tesla, and we are fully capable of synchronously following up the application of this technology. Although Tesla's materials have applied for patent protection, but we can not determine that other materials developed by our domestic manufacturers can not work, we must be clear, no matter what kind of materials are used, some of the basic properties of the materials must be better than the traditional pressed aluminum alloy. For example, the fluidity must be good, because the part is too big, and if the fluidity is not good, it is difficult to even form. In the case of strength and toughness to meet the requirements, each manufacturer can have different characteristics, there are high strength, there is low strength, there is high elongation, there is a low elongation. Our material may not be the best, but it is very adaptable to a certain structure, or a certain process, then our material will be well promoted and applied.
Although entering the era of electrification, the iteration of models has accelerated, and the body is a general trend, but at present, this technology is not mature, and there are still many problems that need to be solved. For example, when a Tesla owner reversed the car, he accidentally crashed the back floor of the one-piece die-cast, and as a result, he spent 280,000 to buy a model y, and the maintenance fee alone needed 200,000. This is where the current integrated die-casting technology is most criticized, once a collision occurs, resulting in damage to the integrated die-casting parts, it can only replace the entire part.
This is why Tesla should first do it on the rear body, they feel that the possibility of collision in that place is relatively low, it is reasonable to say that integrated die casting can reduce the welding point, structural strength and stability should be better than stamping and welding, and Tesla himself said, their materials can make the overall mechanical performance increase by 20% - 30%, can meet the requirements of the collision, but these are better we do not feel personally at present. So more and more consumers began to question whether this new technology is based on sufficient safety and excellent performance, is it cutting leeks?
First of all, the cost reduction effect of this technology is very obvious, and the most direct benefit for consumers is that they can buy electric vehicles at a lower price. In promoting the rapid popularization of electric vehicles and squeezing the living space of foreign fuel car giants, I chose to take the side of Musk, and China and Tesla are on the same front. Secondly, domestic manufacturers have quickly followed up the application of this technology, and the technology of large tonnage die casting machine is also in our hands, so from the perspective of being conducive to the development of China's electric vehicle industry, we do not need to sing and oppose this technology.
Most of the voices opposed, mainly worried that the die casting process is difficult to meet the quality requirements of the automobile industry, such as large hidden dangers of stomatal defects, low precision, difficulty in overall strength coordination, as well as soaring maintenance costs and insurance costs... These problems do exist, and what they say is the truth. My understanding is that Musk wants to make the car a mobile phone-like FMCG product at a lower cost, and it is best to replace it directly with a new one. But it is still too early to say that it is cutting leeks, after all, the technology is not yet mature, and there is still a lot of room for improvement in materials and processes. Just as electric vehicles were first called IQ taxes, now more and more people are embracing electric vehicles, so we need to give more encouragement and patience, rather than strangling them in the cradle because of fear. (Written by self-work number: industrial science and technology control)