As compared to other methods and materials, Liquid Silicone Rubber (LSR) injection molding offers innumerable benefits for automotive parts and components that have high volume demands.
Liquid Silicone Rubber (LSR) 2-Shot (LSR/Thermoplastic) and LSR overmolding processes allow for the integration of multiple parts and materials into one component, thereby minimizing or eliminating additional assembly and quality assurance costs.
With the LSR 2-Shot process, LSR is molded directly onto a thermoplastic component in the same mold that the plastic component was produced; primer is not required. In the case of the overmolding process, the substrate, whether it be metal or plastic, is placed in the LSR mold where it is then overmolded with LSR; depending on the materials involved pretreatments may be required.
From ring seals, single-wire seals, and housing seals to individual inner grommets, these parts are vital to the proper functioning of any vehicle. By employing LSR 2-Shot (LSR/Thermoplastics) technology, the housing, grommet, and ring seal can be manufactured in the same injection molding unit thereby ensuring high-precision parts, while at the same time reducing assembly costs.
Self-lubricating material is ideal for grommets, single wire seals, and many other seals and gaskets where lubricity is needed for ease of assembly. Self-lubricating LSR reduces stick and improves slippage for parts such as housing seals, part o-rings, and other parts that are continually in motion.
These specialized, durable o-rings are used in seat heaters for luxury vehicles. Liquid Silicone Rubber (LSR) injection molding is perfectly suited for high volume, high precision parts that must be durable, long lasting (parts that need to last for the lifetime of the vehicle), and resistant to high temperatures. This technology is also ideal for parts with unique geometries, whether simple or complex.
Even when exposed to oil and many other harsh chemicals, LSR’s mechanical properties will remain the same for the lifetime of the part. With LSR injection molding technology, pressure actuated components such as back flow valves can be designed and consistently produced with uniform thickness throughout the part. Parts such as this can be integrated with other parts or components using LSR 2-Shot injection molding processes, thereby improving part function while reducing or eliminating assembly costs.
LSR’s transparency, pliability, and smooth feel are ideal for buttons that need to allow for the flow of light. With LSR 2-Shot (LSR/Thermoplastics) injection molding technology we are able to design and produce a single component that incorporates both the transparent, flexible buttons and the rigid plastic housing required to protect the electrical components.
Ring seals, single-wire seals, housing seals, individual inner grommets, etc. are all responsible for providing watertight seals that last for the lifetime of the vehicle. These parts must be able to withstand high temperatures without detriment to the part’s mechanical properties. These seals/grommets can be produced using self-lubricating LSRs to allow for easy assembly. In some cases, LSR parts such as these can be overmolded directly onto other components within the assembly thereby creating a superior seal while eliminating assembly steps and time.
Any soft-touch button or component, such as lighted panel buttons, can be designed to feel as smooth as leather, or to provide a messaging sensation by adding tactile rib features or textured surfaces. With careful material selection, soft-touch silicone can be molded directly onto a plastic surface, creating a very strong chemical and mechanical bond.
Automotive exterior components are constantly exposed to a vast range of temperatures. Due to LSR’s ability to maintain its mechanical properties when faced with extreme temperatures (with thermal stability from -50˚C to 250˚C), it is the ideal material for high temperature headlight and/or flexible spotlight gaskets. Its superior elongation and tear resistance, as well as its o-zone and UV resistance are a plus.
It is a good idea to consider LSR for seals or gaskets used in many engine or interior components. For high temperature conditions, or where exposure to radiation or heat may lead to rapid aging, LSR will outperform many of the alternative, available materials. With the proper design, these seals or gaskets can be incorporated into an LSR 2-Shot (LSR/Thermoplastics)/ multi-component part thereby reducing or eliminating all assembly costs.