With the continuous acceleration of automotive intelligence and electrification, the application of various sensors in automobiles is becoming increasingly widespread. The detection of multiple key parameters, including vehicle speed, temperature, pressure, and ambient light, relies on the stable operation and precise measurement of sensors. Sensors themselves usually require good protective measures to withstand external vibrations, temperature changes, moisture, and other environmental factors. Among them, thin-layer encapsulation technology, as a commonly used packaging method, can not only prevent dust, moisture, and shock, but also effectively protect internal components and improve the durability and reliability of sensors.
Technical Challenges and Requirements Analysis
There are several key challenges in the encapsulation process of automotive sensor cavities, including:
Adhesive problems of multiple substrates
Automotive sensor chambers are typically made of materials such as PA66+30GF (polyamide 66 reinforced fiberglass) and stainless steel. There are significant differences in the physical and chemical properties between the two materials, which places extremely high demands on the adhesive performance of the glue. Traditional adhesives often have limitations in their bonding performance, as they cannot form a strong bonding interface with both plastic and metal, which may lead to delamination and leakage during long-term use.
High airtightness requirements
Automotive sensors face harsh conditions such as high temperature, low temperature, and pressure changes from the external environment during long-term operation, and it is necessary to ensure that the sealed cavity has good airtightness. According to the process requirements, the airtightness test needs to reach 35KP, which puts higher demands on the sealing performance and environmental resistance of the adhesive.
Depth control of thin-layer sealing
Due to the sealing depth of only 3mm, the adhesive needs to have moderate fluidity and viscosity during the sealing process, which can ensure uniform filling and prevent overflow or bubble phenomenon caused by overcurrent. Traditional adhesives often struggle to meet both fluidity and adhesion requirements when applied in thin layers, which requires the selection of a product specifically designed for this purpose.
Elaplus Solution
RTV SIPC 1822 neutral dealcoholized silicone adhesive sealant is a flowable moisture absorbing cured silicone gel that forms a flexible rubber body after curing, fully complying with the EU ROHS directive requirements. During the curing process, alcohol substances are released, which are non corrosive to materials such as polycarbonate (PC) and copper. They have good adhesive and sealing properties for the vast majority of materials, protecting electronic products in a stable state under harsh conditions.
The cured elastomer of RTV SIPC 1822 silicone adhesive sealant has the following characteristics:
■ Single component, easy to use, short non stick time
■ Excellent chemical resistance
Resistance to moisture, dirt, and other atmospheric components
Reduce mechanical stress and tension caused by mechanical, thermal shock, and vibration
Excellent electrical insulation performance and anti corona
Excellent outdoor aging resistance, with a service life of up to 20-30 years
Stable mechanical and electrical performance between -60-200 ℃
Looking ahead to the future, with the continuous advancement of automotive intelligence and electrification technology, the requirements for sensor packaging processes will inevitably become more stringent. Yilian will continue to be committed to the research and development of process technology and the improvement of product quality, actively introducing and applying new high-performance materials, and contributing more wisdom and strength to the development of the automotive electronics field. At the same time, this successful case also encourages more companies to pay attention to the detailed management of packaging processes, promoting the entire industry to move towards higher levels of technology and quality.
Tags: Sensor Encapsulation, Sensor Chamber Encapsulation, Automotive Sensor Encapsulation, Thin Layer Encapsulation
