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Tesla has developed an integrally formed frame,which saves a lot in terms of time and manufacturing costs.It seems like a positive advancement,so why hasn’t integrated die casting become widespread in the automotive industry?

In fact, the biggest issue with integrated die-casting is its inability to achieve "flexible production," which has prevented its popularization!

Ⅰ.Let's Look At The Traditional Production Process:Stamping + Welding

1.Stamping Process

Stamping is a forming process that uses presses and dies to apply external force to sheet metal,strips,pipes,profiles,etc.,causing plastic deformation or separation to obtain workpieces(stamped parts)of the required shape and size.

Simply put, stamping takes steel plates as input and produces profiles as output.

2.Welding Process

The automotive body welding process essentially involves assembling and welding parts into assemblies or components,which are then combined to form an overall structure. An automotive body welding structure may consist of dozens to hundreds or even thousands of parts,making the welding process highly complex.

The image below shows stamped sheet metal parts being fixed on welding fixtures and then spot-welded to form a framework.

Of course, many production lines now use robots.The biggest advantage is stable welding quality, high production efficiency, cost savings and the ability to achieve flexible production. A single robotic welding line can perform programmed welding for different vehicle models. When model A comes in, the robots weld the solder joints specific to model A; when model B arrives,they switch to welding those for model B.

This reflect the advantage of traditional production process: a single factory workshop can produce up to 5 vehicle models.Moreover, traditional processes allow for quick transitions with minimal investment. Switching to a new model only requires replacing welding fixtures and reprogramming robots,which can be completed with an investment of around one million RMB for the welding process.

Ⅱ.Integrated Die Casting Requires Huge Investment for New Models;High Transition Costs If Sales Are Poor

Die casting is a special casting technology.Currently,die cast aluminum alloy products account for approximately 54% to 70% of aluminum used in automobiled. Integrated die casting technology represents a new revolution in die casting. It redesigns multiple independent parts that originally required assembly and uses extra-large die casting machines to produce complete components in a single die casting operation, maintaining the original functionality.

1.Advantages Of Integrated Die Casting

1)Weight reduction:Against the backdrop of the double carbon goals,lightweighting is a major trend in the automotive industry. The application of integrated die casting helps achieve lightweighting. Tesla’s early Model Y rear floor assembly saw a 30% weight reduction after adopting integrated die casting

2)Efficiency improvement:Compared with existing production process, integrated die casting simplifies production procedures to increase cycle times, thereby enhance production efficiency.

3)Cost reduction: The use of integrated die casting technology can lower production, land, labor, and other costs. For the rear floor of Tesla’s vehicles,which first adopted integrated die casting, the manufacturing cost decrease by 40% compared to the original process.

2.Disadvantages Of Integrated Die Casting

1)The core of integrated die casting technology lies in heat free materials. While these material avoid the “hassle” of straightening caused by heat treatment, they also lose the opportunity to obtain”stronger mechanical propertied and adjust the balanced crystalline structure of the alloy” through heat treatment. Larger workpiece sizes and more complex shapes further exacerbate these issues. This is why Tesla initially applied integrated die casting to the rear floor, a position with a lower collision probability.

2)More importantly, the large die casting machines used for integrated die casting often cost over 100 million RMB per unit.Additionally, a set of molds for automotive integrated die casting machines costs approximately 10 million RMB. This is completely on a different scale from the 1 million RMB investment required for traditional process transitions mentioned earlier.

Furthermore, the automotive industry relies on economies of scale for profitability. Most enterprises are already on the verge of survival. Not only do they lack the capacity to make upfront investments of hundreds of millions of RMB, but their sales volumes also cannot support such high mould cost.

Therefore, for most auto manufacturers, lunching a new model does not guarantee certain sales figures. They are simply unable and unnecessary to follow this trend. Instead, sticking to their own route of ”flexibility and quick transition” is the best choice.

Flexibility and quick transition are the fundamental keys to survival. This is why few enterprises have adopted integrated die casting.