Most substrate materials in as-received condition (unprepared) are not receptive to adhesives and therefore require some form of surface pretreatment to improve their adhesion characteristics.
Surface pretreatment processes broadly fall into the following categories:
Mechanical
- Cryoblasting
- Gritblasting
- Peel-ply
- Silicon carbide abrasion
- Sodablasting
- Water jet
- Wire wool
Chemical
- Acid etching
- Anodising
- Detergent wash
- Primer
- Solvent cleaning
Physical
- Corona discharge
- Excimer laser
- Flame
- Plasma
For demanding applications combination of above pretreatments may be used to achieve optimum surface condition for initial adhesion and long term durability of bonded joints.
