Industry energised – e-mobility as a ticket to CO2 neutrality

Their march of triumph is unstoppable: a growing number of electric-drive vehicles have come to market all around the globe and represent an important element in achieving the Paris climate targets agreed to by 195 countries. In fact, mobility has to join forces to be climate-neutral at the latest by 2050. To do so, the automotive industry has had to face the most profound restructuring process in its history: letting go of the combustion engine and moving towards alternatives, such as plug-in-hybrid vehicles (PHEV) or battery electric vehicles (BEV).

The electric vehicle, however, is in no way an invention of the 20th or 21st century. Its history began long ago sometime between 1832 and 1839. At that time Scottish inventor Robert Anderson developed the first electric vehicle in Aberdeen. In 1888 in Coburg, the ‘Flocken Elektrowagen’, a four-wheeled electric car, was built, which most likely can be considered the first electrically driven passenger vehicle in history. At the beginning of automotive history—after steam-powered vehicles, but before internal combustion engine vehicles—electric vehicles were technically superior to their competitors in several respects. Nevertheless, they disappeared from the streets around 1910 due to the rapid development of the internal combustion engine and formed a niche market for nearly a century.

It wasn’t until the 1990s that research increasingly became interested again in new battery technologies and electric drives. The reasons were obvious: rising air pollution in urban centres, oil supply problems and the need to curb climate change. And so, in 1997, Toyota Prius was the first large series model with a hybrid drive and thus a successful pioneer in paving the way for further developments.

When American manufacturer Tesla entered the market, the trend really started to pick up speed: in the 2000s, established manufacturers developed a taste for electric vehicles and started to reposition themselves on the market with small series, prototypes, as well as widely available models. Variety grew as did the need for processes suitable for mass production including the necessary tools and materials. Being a keen observer of market trends and a close partner of the key industries, CERATIZIT was able to offer fully-fledged solutions already at that time.

Thanks to intensive development efforts in the automotive industry, the share of full electric and hybrid models has witnessed a clear increase: the latter has grown slightly by one per cent, although 69% of the cars of this type on the world market are vehicles that run entirely on electricity (BEV) and the percentage continues to increase. In the first half of 2021 2.65 million new BEV and PHEV were sold worldwide, meaning that the market share of total unit car sales has grown by 6.3%. Incidentally, the share of electric cars in Europe is already 14%. For 2021, experts forecast a volume of 6.4 million BEV/PHEV throughout the world, which would raise the number of electrically driven cars and light-duty vehicles to a total of around 16.4 million. 

At the same time, the variety of vehicles with an electric or partially electric drive is growing. In the meantime, around 100 models are available in mass production, with 265 passenger cars being produced in medium and small series in 2018/2019 and introduced on several markets in the world. Apart from that, there are another 80 car models which have been specifically optimised for urban traffic and reach a maximum speed of 60 km/h.

An electric motor uses the attraction and repulsion forces of magnetic fields. Therefore, the motor of an electric car consists of a stator, which is a stationary part, and a rotor, which turns inside it. The magnetic field is generated in both parts by current-carrying coils, where the alignment of the alternating attracting and repulsing magnetic fields also changes with the direction of the current. How can a car be moved in this way? Switching the polarity of the coils several times during one rotation of the rotor makes the latter turn continuously. This rotational movement is used in electric cars to drive the wheels, so the car starts moving—driven by electric power.

And where a sometimes extremely complex drive used to be necessary for conventional vehicles in terms of the right amount of torque, this is irrelevant in the case of electric cars. Electric motors cover a much wider speed range and can thus use maximum torque from a standing position. The clutch is also a thing of the past. Instead, the cars are fitted with a reduction-gear system, which gets by with only one gear and a fixed transmission. So, it’s not possible to drive backwards? Of course it is, but there is no need for a separate reverse gear.

• Customised advice on the choice of the ideal carbide grade ensures optimised tool life, increased productivity and process optimisation
• CERATIZIT offers the widest range of corrosion-resistant carbide grades available on the market with an extremely broad application range in the fields of stamping, bending, blanking and forming
• The materials are IATF 16949 certified to guarantee secure and reliable processes
• Research in study groups with scientific institutes and partners from electromobility provides access to the latest developments and trends
• CERATIZIT has a strong R&D department which develops innovative customer solutions, perfectly adapted to the challenges of electromobility
• Thanks to solutions made from tungsten carbide, ceramic or carbide-ceramic composites, CERATIZIT offers high flexibility for every application

The fact that the share of components to be machined in hybrid and full electric cars is lower than in conventional automobiles, does not mean that the remaining machining processes are automatically easier. The housing of electric motors, which consists of various combinations of aluminium alloys, is of particular interest for cutting tool experts. The focus here is increasingly on the unit costs, particularly those for the stator hole, which is the most costly part, placing high demands on tools and cutting edges. For drilling diameters of 200 mm and more, weight reduction plays an essential role in not exceeding the maximum stall torque and drive torque of the machining centres used. 

Innovative solutions also make the difference when it comes to electric motor housings. The PCD face milling cutter MaxiMill SEC12 is the ideal tool for the automotive industry when aluminium or non-ferrous metal components have to be machined whose internal surfaces must be absolutely free from chips. Thanks to the special design of the insert seats and cutting insert topology supported by the coolant pressure, a suction effect is created at high revolutions which removes almost 100% of the chips from the workpiece.

To ensure long service life and safe storage, the batteries of electric and hybrid vehicles are frequently stored in high-tensile aluminium battery trays as these are not much of a factor in terms of weight. In order to keep costs within limits, durable and innovative tooling systems are preferred for the huge amount of holes and threads. For example, systems which are able to perform several different cutting processes. For the sake of efficiency, the speed may be increased in the case of the long contact faces of the battery tray lid – HSC and HPC tested and proven milling tools reach new speed records in this field.

Who says that motor racing always means large-volume combustion engines with deafening noise for best lap times? Formula Student, a racing league especially for students, has shown that this does not have to be the case with a category of full electric race cars. An extremely successful team in this field is the Green Team from Stuttgart University, who pulled their E0711-11 EVO vehicle up to the starting line for the 2021 season. But until they could do that, some obstacles in terms of construction had to be overcome.

An analysis showed that the required tolerances could not be achieved with a standard solution. So the team developed a customised solution: an additively manufactured tool with two adapters for inserts and a vibration damper which is mounted on the U-axis. ‘With over 120mm component diameter and a 5-axes machine with a HSK63 connection, there was no way around reducing the load on the spindle,’ says Haudeck. The light FEM-optimised design optimally absorbs the forces occurring during the cutting operations and makes machining in one set-up possible. Was it worth the effort? Absolutely. The team won two out of four races in the past season and placed second once—not least thanks to the support of CERATIZIT.

Sustainability is firmly anchored in CERATIZIT’s company approach. For this reason we are at the forefront when it comes to promoting resource-efficient technologies and to establishing them in the long run. That’s why we think that whoever wants to remain mobile in the future with a clean conscience cannot ignore e-mobility. Developments are moving forward whether it be the range of full electric cars or the nationwide distribution of the recharging infrastructure. In order to give the necessary impetus, we at CERATIZIT do the research ourselves or work together with technology partners and customers to constantly develop new concepts for a CO2-neutral mobile future. What is required is to show new and sustainable paths to competitive solutions, develop and implement innovative technologies, and effectively promote groundbreaking trends. This includes digital services such as ToolScope, the effective monitoring tool from CERATIZIT for process security in machining operations. In this way, we can work together to achieve the climate targets we have set and thus preserve our planet for future generations.