Tesla integrated die casting major breakthrough! Developing a new car may only take a year and a half Three major technical roles

"Science and Technology Innovation Board Daily" on September 15 (editor Zheng Yuanfang) According to foreign media citing five people familiar with the matter, Tesla has made a technological breakthrough in integrated die-casting, which will be the key to Tesla's production of tens of millions of affordable electric vehicles in the next decade and the realization of profit plans.

With this breakthrough, Tesla can die-cast nearly all of the complex underbody parts of an electric car into a single unit, instead of just about 400 parts.

The new technology is at the heart of Tesla's "Unboxed Assembly Process" assembly system, which Tesla said when it announced in March that it would support the production of lower-priced models and is expected to reduce the production cost of electric vehicles by 50 percent and reduce factory space by 40 percent.

With this new technology, Tesla can develop a car from scratch in 18-24 months, compared to 3-4 years for most of its current competitors, the sources said.

Tesla has been planning a small electric car for $25,000. The report pointed out that the model may use an oversized casting frame to combine the front of the car, the parking space, and the underbody (where the battery is placed). Tesla is expected to decide whether to do so as soon as this month, and the final product may also change during the design verification process.

Terry Woychowski, president of Caresoft Global, an American engineering company, believes that if Tesla can integrate most of the chassis parts, it will further subvert the way cars are designed and manufactured. "This is an extremely powerful enabler with huge implications for the entire industry. But it is also an extremely challenging task, and castings are very difficult to make, especially larger and more complex castings. ”

▌3D printing, industrial sand and custom alloys

Tesla's breakthrough lies mainly in two aspects: one is how to design and test giant molds for mass production; The second is how the casting combines hollow subframes with internal ribs to reduce weight and improve crashworthiness.

The two innovations, jointly developed by multinational design casting experts, involve the use of 3D printing, industrial sands and custom alloys.

In fact, "one-in-one die-casting larger parts" has always been a challenge for automakers: making larger molds does improve efficiency, but it is expensive and carries countless risks.

One casting expert said that once a large metal test mold is made, each adjustment to machining during the design process can cost $100,000, while a complete redo of the mold can cost $1.5 million. Another said the entire design process for large metal molds typically costs about $4 million. As a result, most automakers are deterred. Because in terms of noise and vibration, assembly and surface treatment, ergonomics and crashworthiness, it may take at least six adjustments to design the perfect mold.

Despite the risks and difficulties, sources pointed out that Musk's original vision was to find a way to integrate die-casting the entire body underbody.

To this end, Tesla turned to companies that use 3D printing and industrial sand to make test molds, using digital design files, using binder jets to deposit liquid binders onto thin layers of sand, layer by layer to build molds that can die-cast molten gold.

Even with multiple versions, the design verification process for sand casting is extremely costly, at just 3% of metal prototypes — meaning Tesla can tweak the prototype as many times as needed and reprint a new prototype within a few hours, according to one source.

The cost advantage is on the one hand, on the other hand, after using sand casting, the design verification cycle only takes 2-3 months, while the metal mold prototype takes 6-12 months.

In addition, the subframe of the car chassis is usually hollow to reduce weight and improve crashworthiness. In order to cast the hollow subframe, Tesla plans to place the solid sand core printed by the binder jet machine throughout the mold, and when the part is die-cast, the core is removed, leaving voids.

However, in this process, due to the different performance of the aluminum alloy originally used to produce castings in the sand mold and metal mold, it could not meet Tesla's crashworthiness and other standards. Therefore, casting experts overcome this problem by making custom alloys.

Once Tesla finalizes the prototype mold, it can invest in manufacturing the final metal mold for mass production.

▌Tesla's new models provide excellent opportunities for use Many car companies have followed up on integrated die-casting

Tesla is currently developing two small cars: one for personal use and the other for the Robotaxi. Sources pointed out that their underbody structure is relatively simple, which also provides an excellent opportunity for Tesla's new technology to be used.

Of course, if Tesla decides to integrate the die-cast body, it must decide which die-casting machine to use, and this choice will also determine the complexity of the car's frame - in order to quickly die-cast such a large part, Tesla needs a new, larger die-casting machine, clamping force of 16,000 tons or more, which is more expensive, and may require more factory space.

However, the high clamping force could not accommodate the 3D printed sand core required to create the hollow subframe. People familiar with the matter said that Tesla can solve this problem by using different types of die-casting machines. This method allows the molten gold to be injected slowly, which tends to produce higher quality castings while accommodating the sand core; But this process takes more time.

Tesla has always been a solid fan and practitioner of integrated die-casting. According to the information released by the company, after adopting integrated die-casting technology, 80 stamped and welded parts of the original Model Y solution can be integrated into one casting, and achieve 40% cost reduction and 10% weight reduction.

It is worth noting that most of the new energy vehicle companies that followed Tesla to join the integrated die-casting team were NIO, Xiaopeng, and Lili, and there were few traditional car companies. Today, in addition to Toyota, General Motors, Hyundai Motors, Volvo Cars, etc. have also begun to plan to adopt this technology.

Implemented in the overall industrial chain, Guotai Junan believes that the upstream is composed of heat-free aluminum alloy materials, die-casting machines and die-casting molds, with an integrated die-casting mold gross margin of 40% and a net profit margin of 20%, the highest single-link profit, the highest technical barriers, and a scattered pattern; Midstream is a third-party die-casting plant and a vehicle manufacturer with its own production line, which is highly competitive, and a small number of aluminum casting suppliers with core advantages occupy most of the supporting market for mid-to-high-end models; The downstream is directly connected to the main engine plant.

Minsheng Securities also pointed out that integrated die-casting products are expected to expand from rear floor products to front cabin, middle floor plate, battery tray and other related parts, it is recommended to pay attention to iKedi, Xusheng Group, Wanfeng Aowei, Ruihu Mold, Meilixin, Rongtai Co., Ltd., Bojun Technology, Dolly Technology, Xiangxin Technology, Huada Technology, Wencan Co., Ltd., Guangdong Hongtu, Lizhong Group, LK Technology, Yizumi, Xingyuan Zhuoma, Heli Technology.