Tribology of innovative polybenzimidazole (PBI) coatings

Polybenzimidazole (PBI) was prepared as thin coatings on aluminium substrates at different final curing temperatures. Their tribological properties were tested at room temperature in comparison to coatings made of polyamideimide (PAI), using various test methods. The adhesion to the substrates was best for PBI processed at a final curing temperature of 280°C. This was also reflected in a better scratch resistance, whereby in all cases PBI was superior to PAI. The same was true for sliding wear of the coatings against smooth steel counterparts. Under abrasive wear against sand paper, the friction and wear values were lower for smaller abrasive grains, but no remarkable differences were visible between PBI and PAI, regardless of the curing temperature.Polybenzimidazole (PBI) was prepared as thin coatings on aluminium substrates at different final curing temperatures. Their tribological properties were tested at room temperature in comparison to coatings made of polyamideimide (PAI), using various test methods. The adhesion to the substrates was best for PBI processed at a final curing temperature of 280°C. This was also reflected in a better scratch resistance, whereby in all cases PBI was superior to PAI. The same was true for sliding wear of the coatings against smooth steel counterparts. Under abrasive wear against sand paper, the friction and wear values were lower for smaller abrasive grains, but no remarkable differences were visible between PBI and PAI, regardless of the curing temperature.