LANXESS develops radar sensor concept with integrated thermal management

LANXESS, one of the leading thermoplastic high-performance polymer suppliers, sees itself as a development partner for New Mobility
.
The specialty chemicals group has developed a new concept for radar sensors with integrated thermal management, which will benefit autonomous driving
.
Although there is still a long way to go, driver assistance systems are increasingly becoming a key feature in future generations of vehicles
.
The 360-degree monitoring of the surrounding environment of the vehicle is achieved by radar waves and the like
.
Radar sensors are an important part of distance control, lane change monitoring, collision avoidance and blind spot monitoring systems, among others
.

The sensor must be dust and water resistant and is therefore designed as a fully enclosed system
.
But this makes it difficult to dissipate heat efficiently from the inside, which in turn compromises the performance of the electronics and the durability of the sensor
.
Gregor Jaschkewitz, application developer in the High Performance Materials (HPM) business unit at LANXESS, said: "This is why we have developed a concept that allows heat dissipation by combining thermally conductive plastics with metal cooling elements
.
The individual sensor components use integrated snap-fits Assembling with hot rivets is much less costly and time-consuming than using screws
.
”

low number of components

For radar sensors, this new concept from LANXESS involves the following individual components: the front cover ("radome"), the radar absorber, the PCB (including the antenna) and the rear cover with integrated cooling elements
.
The radome faces the vehicle and must use plastic that is highly transmissive to radar waves
.
Polybutylene terephthalate (PBT) is a very suitable material because of its low dielectric constant (Dk) and dissipation factor (Df)
.

Functional integration through hybrid technologies

The back cover is the most complicated part of the whole assembly
.
It is manufactured using plastic-metal composite (hybrid) technology with polyamide 6 and a metal cooling element
.
This allows engineers to take advantage of the enormous design freedom offered by the injection molding process, allowing them to incorporate features such as reinforcement and cooling ribs, as well as notches for strain relief connections for connectors and cables
.
Most importantly, however, the surface of the metal cooling element can be overmolded with a thin area of ​​plastic
.
The heat generated on the PCB electronic components can be effectively dissipated from the entire assembly through these plastic areas
.
Jaschkewitz said: “The thermally conductive polyamide 6 in our Durethan BTC product range supports this effect as an injection moulding material
.
Polyamide 6 is also extremely tough and ductile
.
Another benefit of the hybrid design is that the metal cooling elements can The electronic components inside the radar sensor are shielded from electromagnetic radiation, which means that their function is not affected by external radiation
.
The assembly can be performed with O-rings or sealing lips produced in a two-component injection molding process Sealed
.
"

Customized Material Combinations

In most plastic radar sensor concepts, the radome and back cover are traditionally always made of thermoplastic and can be welded to each other to form a fully enclosed assembly
.
This usually means that the same plastic must be used to connect the two parts
.
"However, our approach is less restrictive in material selection and easier to use with custom compounds," Jaschkewitz said
.

Benefit from the expertise of global development partners

Lanxess believes that sensors for driver assistance systems will offer plenty of opportunities for its Durthan polyamide and Pocan polyester
.
Dr.
Christopher Hoefs, Global Application Development Specialist at LANXESS' High Performance Materials business, said: "We want to benefit from the huge growth potential in this application area and advance technological innovations with our own ideas - such as the concept of radar sensors
.
For example, The business unit also recently unveiled a modular design concept for EV charging connectivity.

HPM has brought together its extensive knowledge of materials, applications, processes and technology development under the HiAnt brand to support partner and customer projects
.
We support our partners in all stages of application development - from conceptual design, material optimization, mechanical and rheological simulations to component testing and the start of series production
.
"