Corrosion test during extrusion
High performance polyamides are processed at high temperatures (> 300°C) and often are processed with non-halogenated flame retardants and glass fibers. The impact of wear and corrosion can be measured dynamically on a special testing device. The polymer was processed through the test tool inserts and the weight loss was measured after processing each 25 kg of the melt.
Non-coated steel inserts
After 25 kg processed compound the inserts had suffered a considerable weight loss due to corrosive attack.
Inserts coated with 5 different sputter coatings from CemeCon
After 100 kg processed compound no optical changes are seen, and no weight loss could be measured on any of the coated inserts.
Corrosion test in acid
Coated metal rods where subjected to powerful acids to assess
the protective capacity of different coatings
Corrosion test in phosphoric acid
Standard coating: Fatal chemical attack removed the coating and the base materia
CemeCon coating: Chemical attack limited to the spots on and beneath the coating
Corrosion test in sulfuric acid
Standard coating: Severe chemical attack practically removed the coating
CemeCon coating: Chemical attack limited to a few spots in the coating