Measurement of appearances of oxide residues on rolled metals,

摘要

Abstract: Oxide residues on rolled aluminum sheets appear as blemishes which deteriorate aesthetic surface quality. Consequently, the relative severities of surface oxides must be evaluated for product quality control, especially in packaging applications. In the current practice, an experienced QA person visually inspects sheet surface for oxide residues and assigns a grade based on the apparent severity. This procedure is limited by the ability of the operator to resolve varying levels of oxides, and inspection results vary from operator to operator. This paper presents an imaging technique developed to measure undesirable oxides on metal surfaces. The technique provides quantification of oxide severity with potentially finer resolution and improved repeatability than currently possible. Preliminary results from the evaluation of oxides on cold rolled aluminum samples show that oxide severities quantified using this technique correlate well with the discrete grades assessed by QA personnel. !3