Interim Manager, innospiration
Magnesium in Die Casting Lightweight Design - Economical Even in Small Series
Not only racing drivers can benefit from individual lightweight solutions. Sidrag AG has set itself the goal of closing the gap between the prototype workshop and mass production by manufacturing small and medium-sized batches.
"Lightweight design is the key to success in motor racing. Especially in the case of e-mobility, this is a major issue due to the extra weight of the battery," says Nico Müller, Audi Sport factory driver in the DTM and Formula E, "Every gram counts. At this power density, 10 kg already cost 0.2 seconds. The formula for success is lightweight design".
Lightweight Design Saves Energy
According to experts, the production of lightweight design elements will increase by 400 % during the next eight years. For example, with a weight of 1,600 kg and a fuel consumption of 8 litres per 100 km, 1.12 litres per 100 km could be saved if the vehicle was 112 kg lighter. For instance, an Airbus would consume 10,000 litres less kerosene in one year if it was 100 kg lighter. A look at the automotive industry shows that seven years ago only 6 kg of magnesium was used per vehicle. Experts expect up to 100 kg of magnesium per body by 2020.
What Are the Advantages of Magnesium?
The higher price per kilo of magnesium compared to aluminum discourages many companies. Due to the lower density, however, the volume price is almost identical. Magnesium is the lightest technical metallic construction material — the density is only 63 % of aluminum and 38 % of titanium. It is more heat-resistant than plastic and provides a high shielding capacity against electromagnetic interference. Due to the high elasticity of magnesium, vibrations can be absorbed even with large and thin-walled parts. Magnesium components require surface protection and can be painted or powder-coated in various processes. The light metal also offers a major advantage in terms of availability: even seawater contains 1 kg of magnesium per cubic meter. Further advantages are a high-quality metallic appearance and perfect recyclability.
Light Metal Processing in SMEs
Die casting foundries are usually a symbol of mass production, especially in the automotive industry. However, medium-sized companies can also occupy a niche with light metal processing and succeed in a highly competitive market. The 50-man Sidrag AG took a different path and positioned itself as a specialist for small and medium-sized series. With less automation, but all the more flexibility from experienced employees. Many global corporations therefore have their aluminum, magnesium or zinc components manufactured by the small and medium-sized enterprise in the middle of Switzerland.
"Of course, the question of China is always raised in discussions with customers," Eugen Vigini, CEO of Sidrag AG, tells us, "From a cost perspective, this is certainly worth considering. But only for very large series. In terms of flexibility, especially for short-term demand and quality, Switzerland as a location in the heart of Europe is unbeatable.
Since customers are expecting the most comprehensive problem solution possible, it is no longer enough to simply produce high-quality die cast parts. This starts as early as during the design phase with a qualified consultation of the product developers, a close support by experienced project managers, continues with the CNC post-processing and is followed by the network of coating specialists. As a result, customers receive ready-to-install components. "The magic formula is to integrate functions and optimize the supply chain," adds company coach Raimond Gatter. Small foundries in particular are struggling with steadily increasing costs and emerging trends such as 3D printing. But in what cases is it more favorable to cast light metal components or to produced them in a 3D printer?
Rapid Prototyping vs. Die Casting
Rapid prototyping processes such as 3D laser sintering are particularly suitable for individual prototypes up to small series of approx. 30 items. Rapid prototyping is a more economical alternative, especially if many modifications are involved or the design still has to be changed and adapted. A further advantage is the procurement time of usually just a few hours to days until the first prototype is ready. For larger quantities and depending on the part weight, additive manufacturing loses its advantages: on the one hand, high costs are incurred for the metal powder required. On the other hand, 3D printing is still very time-consuming. Due to the fire hazard, magnesium components cannot yet be produced using laser 3D printing by the current state of the art.
For small series for field tests and trials, die casting pays off for series comprising as little as 30 pieces. Even if, in contrast to printing processes, a mold is required, the total costs are usually below that of 3D printing or machining processes. Magnesium can also be processed without any problems. A further advantage is that the components are already ready for later series production in die casting and the design does not have to be reworked subsequently with chamfer milling etc.