Automotive
Modern engineering adhesives are a revolution in car manufacturing
By Shunan Li, APAC BDM for Automotive Electronics at Bostik T
o remain competitive in the fast-growing electric vehicle market, manufacturers are striving to increase EVs’ reliability and driving range. With increasing electrification, cars today have over 100 electrical components which control anything from engine performance and fuel efficiency to door locks and parking assistance. To optimize the efficiency of EVs, manufacturers are now looking for ways to further reduce weight and control the temperature of the vehicle’s components. One way is to use modern adhesives and resins in the manufacture of the car’s electronics.
Each car today has a vast array of mini- computers inside of it. These electronics are miniaturized and crammed onto printed circuit boards (PCBs) and into tighter spaces. Some units are now multifunctional such as Power Control Modules (PCMs), which control both the engine and the gearbox, which help reduce the size and makes components lighter; even a 10 per cent decrease in weight can improve the energy efficiency of a car by up to 8 per cent, extending its driving range.
These control units, such as OBC- inverters- and battery- electronic control units (ECUs), need sealants to protect PCBs from water and chemicals. Traditionally pre-molded or die-cut peel-and-stick gaskets were used in manufacturing. Often parts were soldered or welded together. Now sophisticated adhesives, which form lighter liquid seals and gaskets, are considered viable alternatives for automotive and electronic manufacturing and have some distinct advantages. Liquid gaskets provide ECUs with the same protection from water, dust, and chemicals but form more robust seals. They are extremely flexible and don’t crack or deform when compressed. They can also be used in high-precision automated production processes. In a process known as UV Cure- in-Place Gasketing (CIPG), liquid resins such as Bostik’s UV CIPG AU589V and AU060R are dispensed and cured in seconds using UV light to form a permanent seal. That reduces waste, lowers assembly and handling costs,
30 May 2023
and produces a higher quality product. In the future, more ECUs will be needed to enable developments in advanced driver systems, autonomous vehicles, and more sophisticated passenger communication and infotainment systems. But squeezing more components onto PCBs and making multi- functional, power-hungry units like PCMs, increases the amount of heat generated. The liquid gaskets offer protection against temperature fluctuations, a feature which is becoming ever more critical.
Temperature control is vital for the longevity, efficiency, and safety of the different control units which run the battery, motors, onboard chargers, and inverters. Performance decreases if the temperature is too low, but if the temperature is too high, it not only shortens the lifespan of the components but it can also lead to a sudden complete failure and the car breaking down. So today, it is no longer enough for gaskets and seals only to protect components and PCBs from external contaminants; they also need to offer some
protection against higher temperatures. As the heat generated on densely packed PCBs rises, the materials housing them, including the gaskets and seals, will need to be more heat conductive than they are today, helping to dissipate the heat or transfer it away from the PCBs to a heatsink. The adhesives and surrounding materials also need improved electrical insulation, and need to have flame-retardant properties, in the event a component overheats or a car battery catches fire as a result of a thermal runaway. The latest polyamide hotmelts offer a solution. Hotmelts were first developed decades ago but have evolved and been reformulated to improve their heat and electrical conductive properties. A cross between classic plastic injection and resin potting, polyamide hotmelts are ideal for connectors, onboard electronics, LEDs, and PCBs. The process is simple: a metal mold is made, a circuit board is placed inside, and the resin is injected to fill the mold. Hotmelts such as Bostik’s Thermelt Low Pressure Bio-Based Molding Hotmelt for LPM (Low Pressure
Components in Electronics
www.cieonline.co.uk.uk
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66
