APPLICATION TECHNOLOGY Agrati and Atotech’s collaborative drive in the EV industry Agrati and Atotech have created a collaborative drive for an innovative test set-up for the conductivity measurement of coatings in bolted joints.
Innovative test set-up for conductivity measurements
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he rapid evolution of electric vehicles (EVs) is increasing the need for cutting edge advancements in technology. Among these, the conductivity of bolted joints emerges as a critical factor for both performance and safety, particularly in high voltage applications. To address the growing demands of the EV market, and fill the void in the international standards regarding bolted joints conductivity, a joint team from the Agrati Tech Center and MKS’ Atotech experts has been established. The commitment of the joint venture, and to help face the challenges of the rising demand for EV components, was to design, develop and validate an innovative test set-up for conductivity measurement in bolted joints.
Test set-up design
The design of the test set-up takes a fresh approach, focusing on understanding the impact of coatings, counterpart material and clamping force on conductivity in bolted joints. This advanced method leads the way, providing a deeper understanding to optimise coating solutions tailored to the specific needs of the EV market. The set-up is portable, adopting the four wire Kelvin measurement approach, enabling precise measurements, and provides multiple contact resistance measurements. It also measures conductivity versus clamping force and can change counterpart materials to simulate real applications.
Results and insights
Initial examinations and analyses conducted by means of this test set-up have shown promising results. To date, 62 coating systems have been tested, primarily focusing on electrodeposited systems of various
chemistries. Zinc flake coatings have been also evaluated. Considering the capability of measuring multiple contact resistances, 3,500 pieces of data are available so far. Engaging outcomes have emerged using this set-up, such as the impact of sealer composition on final conductivity performances. Interesting findings were also noted concerning black galvanic coatings and the low conductivity performances of zinc flake systems have been confirmed.
Conclusion
The collaborative efforts of Agrati Tech Center and the MKS’ Atotech Team have revealed valuable insights into the conductivity dynamics of bolted joints, setting the stage to achieve the best cost-effective compromise. Further trials are going on with clients for measurements on different materials like copper and aluminium, followed by conductivity evaluation after corrosion tests and aging.
NORMA supplies joining technology for fuel cell trucks
NORMA Group has won an order to supply various joining solutions for the production of fuel cell drive systems – where the joining components are used in the cooling system for the fuel cell racks, as well as on the electric air compressors. This project, from a major German automotive supplier, is the biggest order for fuel cell vehicles NORMA Group has received so far.
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uido Grandi, CEO at NORMA Group, stated: “Hydrogen technology is an important growth area for us. The transformation towards low emission mobility is the major task the automotive industry is facing in this decade. With our profound development experience in the automotive sector, our global production network, and local test laboratories, we can optimally support our customers in the industrialisation of new technologies.” In September 2023 NORMA Group started to deliver the first serial products for installation in trucks of an American manufacturer. Until 2027, a ramp-up of production is planned. More than 170,000 trucks from various manufacturers in the US and China are to be equipped within the next seven years. NORMA Group produces the joining solutions at its plants in Germany, China, the Czech Republic, and the United Kingdom, and from there delivers them to customer locations in Europe, China and the United States. NORMA Group’s metal clamps and rubber profiled retainers can be used to securely fasten rubber hoses, while quick connectors and hose connectors are suitable for leak-proof connections of plastic pipes. Already in 2018, NORMA Group had started supplying a line system for a fuel cell vehicle to a German car manufacturer. Several projects for hydrogen powered vehicles with different tier customers and OEMs has followed in recent years.
154 FASTENER + FIXING MAGAZINE | ISSUE 145: JANUARY 2024