What is Body in White?
Body in White (BiW) is a stage in automotive manufacturing where the non-moving panels in a car’s body have been joined together, but the motor and other sub-assemblies (glass, electronics, chassis) have yet to be joined together. This is the stage where the vehicle’s final contours are worked out through extensive computer simulations before the vehicle is painted.
Why is Body in White Important?
Body in White is an important stage in automotive manufacturing as it is where the vehicle achieves its high tensile strength, stiffness, crashworthiness and occupant safety. Design stages of BiW also concern achieving weight reduction using fibre reinforced composites, durability, corrosion-resistance, and measures against water ingress.
Effective adhesive bonding in the BiW stage, therefore, enables:
- Enhanced torsional stiffness
- Enhanced fatigue strength
- Improved stress distribution
- Reduced cracks around spot welds
- Vibration dampening; therefore improved acoustics
- Seam sealing
- Reduced energy consumption
- Reduced CO2 emissions
- The integration of different composites and metals (magnesium, aluminium, fibreglass)
Preforming is the stage in automotive manufacturing where the constituent materials of body parts are put together, ready to be moulded. Preforming is an important stage in achieving high quality finalised components, leading to reduced maintenance costs in the future.
Composite solutions for preforming
Araldite® LT 3366 is a non-reactive preforming binder ideal for the mass-production of powdered fabrics and preforms. It has a high softening point of 150°C, which prevents ply-to-ply adhesion during storage. Additionally, this allows fibre distortions to be avoided at injection temperatures up to 120°C.
Araldite® XB 6078 is a reactive preforming binder suitable for the production of thick preforms. It is commonly used in the manufacture of leaf springs, as well as the production of highly aesthetic parts. Its softening point is 85°C, and it can be used in injection temperatures up to 160°C.
Sheet Moulding Compound (SMC)
Sheet moulding compound (SMC) is a glass-fibre reinforced material used in compression moulding. It is ideal for applications where high mechanical strength is a requirement; such as automotive engineering. SMC has advantages including high volume producibility, flexibility, great part reproducibility and weight reduction capability. All these factors make SMC a viable material choice in the Body in White manufacturing stage.
Composite solutions for SMC
Araldite®LY 3569 / Aradur® 1571 / Accelerator 1573 / Aradur® 1575 is a composite system with a medium glass transition temperature ideal for Body in White parts. It is capable of processing a wide range of part thickness. This composite system can compound on large-sized SMC rolls, leading to the resulting SMC retaining very good drapability for 6 weeks at 23°C. Overall, this composite system allows for efficient work time and extended vehicle lifespan.
XB 50021 A / Aradur® 1571 / Accelerator 1573 / XB 50021 B is a composite system with a high glass transition temperature, which is ideal for parts close to the engine. It is capable of processing up to medium part thickness. This composite system can compound on medium-sized SMC rolls, leading to the resulting SMC retaining very good drapability for 6 weeks at 23°C.
High-Pressure Resin Transfer Moulding/Wet Compression Moulding
High-pressure resin transfer moulding (HP-RTM) and wet compression moulding (WCM) are two key moulding techniques used in the automotive industry. Advantages of WCM include the ability to apply resin outside of the mould, which frees up equipment for reduced cycle time whilst speeding up resin impregnation. HP-RTM offers a processing system for manufacturing extremely lightweight, high-performance parts.
Composite solutions for HP-RTM / WCM
Araldite® LY 3585 / Aradur® 3475 is a composite system that provides a fast curing solution for Body in White production. It is ideal for reducing cure cycles, improving toughness and enhancing processing.
Araldite® LY 3031 / Aradur® 3032 is a composite system that provides a very fast curing solution for Body in White production. It is ideal for improving productivity and meeting requirements of structural automotive parts made by WCM.