METALLOGRAPHIC METHODS FOR DETERMINING THE QUALITY OF ALUMINIUM ALLOYS

Metallographic investigations are critical in research and materials’ quality control. Therefore, these methods are very present in scientific and industrial activities. In particular for quality control, metallographic analyses have an indirect correlation with quality, time and economic aspect in the metallurgical industry. Most of the metallographic methods used for aluminium alloys’ quality determination are non-standard and are required by customers. The suitability and effectiveness of these metallographic control methods are best determined by interlaboratory investigations. In this investigation, two metallographic laboratories with seven different operators using five different light microscopes with associated software were involved. The interlaboratory analyses covered a determination of the rim zone, dendritic arm space, intermetallic phases and non-metallic inclusions. From the calculated measurement uncertainty, where in the worst case results differ by 4.7 %, it is clear that all four metallographic methods are suitable for implementation in industrial quality laboratories, when correctly and accurately defined (with easy-to-follow instructions).