The future cast from a single mold

New production capacity for e-mobility

Building on its profound expertise in materials and processes, KS HUAYU AluTech is busy carving a niche for itself in future-oriented markets. The engine block specialist is making major inroads in the realm of electromobility. In addition to its core products, the company is now producing battery holders for electric vehicles and structural parts at a new production facility in Neckarsulm, Germany.

What better place to find out how molten aluminum can be turned into solid components than KS HUAYU AluTech GmbH in Neckarsulm? In a newly built 5,000-square meter production hall, the company develops and produces structural parts ranging from bumper brackets and spring struts to cross beams and battery trays. Symbolizing the Group’s foray into new technologies and production techniques, these components significantly expand Rheinmetall Automotive’s core business.

In 2014, the internationally operating auto parts maker melded its fifty-fifty joint venture with China’s HUAYU Automotive Systems – a longstanding partner – into its casting activities in Neckarsulm. A steady stream of successes attests to the joint venture’s excellent cooperation.

The joint venture has made a name for itself in the electromobility market

Among other items, KS HUAYU AluTech has booked major orders for spring strut mountings, rear axle subframes, and wheel carriers, often destined for top carmakers such as Audi, Mercedes-Benz and Porsche.  

Securing a foothold in the world of e-mobility 

In the meantime, the joint venture isn’t just an internationally sought-after specialist for aluminum cylinder crankcases: its cast parts have also helped the company make a name for itself in the new electromobility market. For example, it now makes battery trays for the Audi e-tron and – at its Chinese locations – the electromotor housing for the VW E-Golf in China.

The steadily growing importance of the non-internal combustion engine sector was decisive in leading the company to create additional production capacity at its headquarters in Neckarsulm. Around 35 million euros was invested at the location, resulting in a new casting plant with four pressure casting systems, together with adjacent space for further processing. Since last year, 120 people have been working in the new facility, which encompasses the full production process – from smelting the aluminum to pressure casting, and from heat treatment to CNC post-processing and final inspection. 

An international orientation 

Rheinmetall Automotive’s strategy of relying on its traditional casting expertise and continuing to expand internationally is therefore paying off. With the new hall and a strong international orientation, the Group has taken another important step on the road to its goal of becoming the world’s leading maker of cast components for the automobile industry. 

In Germany, the company now produces some 1.2 million structural and chassis components a year; worldwide, the production figure now tops two million. By 2021, the share of structural parts in the portfolio is supposed to rise to around 35 percent, up from the current 20 percent. The plan calls for making the change while keeping employee numbers constant. In Neckarsulm alone, headcount in the company’s casting activities currently totals 1,100, with annual sales of 320 million euros.  

By 2021, the share of structural components in the product portfolio is expected to rise to 35 percent

Worldwide, the casting joint venture employs a 4,800-strong workforce, spread between Neckarsulm, Walldürn, and Langenhagen (all Germany) as well as six locations in China, where the company is now the biggest maker of aluminum cylinder heads. In the Chinese market in particular, having a local presence is a major competitive advantage, since the OEMs that operate there prefer to source components produced locally. 

Specialists for sophisticated cast parts 

In China, the production of the motor housing for the Chinese E-Golf has been up and running since mid-2018. Featuring built-in cooling, this large component was developed in Neckarsulm, advancing from prototype to series-production readiness. This process was subsequently applied in serial production in the factory in Guangde, West of Shanghai. A highly demanding task, to be sure, but also trendsetting one: Bringing new cast parts for electric vehicles to the market today is creating a key future mainstay for Rheinmetall Automotive’s international casting specialist.

Dr. Jochen Luft, Managing Director KS HUAYU AluTech GmbH


When it comes to aluminum casting, what’s in it for the automobile industry?

A big advantage of aluminum cast parts is that they weigh less than steel components. After all, lots of our customers are eager to reduce the weight of their vehicles. Another big plus of aluminum casting is high functional integration of the parts, plus the potential for creating complex forms. There’s less need for post-processing, too, which means that it offers production advantages compared with steel sheet designs. Finally, we rely on the excellent thermal conductivity of the material when producing battery trays. Aluminum does a much better job than steel of conducting waste heat from a battery into the environment or surrounding water jacket. 

What additional potential do you see for the material?

In the medium term, it might be interesting to use aluminum for producing gear housings for cars and trucks. At the moment, truck makers in particular are very interested in gear and clutch housings from KS HUAYU AluTech, and oil sumps, too. In the next few years, I could also imagine us producing cast aluminum trunk lids, hoods, and side elements. 

That sounds pretty sophisticated. What techniques do you use?

We normally use an aluminum-silicon base alloy with slightly varying alloying elements for our various applications. Cylinder heads are manufactured using gravity die casting, chassis components with low-pressure casting. The best way to make thin-walled and large surface structural parts is high-pressure casting. When it comes to highly complex components with lots of undercutting, like housings for electric motors, we use low-pressure sand casting.  

How does KS HUAYU AluTech stay competitive?

There’s a plenty of competitive pressure in our sector, since lots of casting companies are looking for new business beyond the internal combustion engine.  Thanks to our tremendous experience and excellent processes, we’re extremely well positioned to compete. Listen, large-format structural components aren’t easy to cast – it demands a lot of special expertise. You have to be able to handle 40,000 kilonewtons of pressure during injection, not to mention the rapid solidification of the aluminum alloy. Avoiding air pockets isn’t easy, either. Moreover, you’ve got to make sure the ambient conditions are right, by which I mean temperature and atmospheric humidity. We’re one of the few companies in the world that’s able to do all of these things.