Measurement of appearances of oxide residues on rolled metals

摘要

Abstract: Oxide residues on rolled aluminum sheets appear asblemishes which deteriorate aesthetic surface quality.Consequently, the relative severities of surface oxidesmust be evaluated for product quality control,especially in packaging applications. In the currentpractice, an experienced QA person visually inspectssheet surface for oxide residues and assigns a gradebased on the apparent severity. This procedure islimited by the ability of the operator to resolvevarying levels of oxides, and inspection results varyfrom operator to operator. This paper presents animaging technique developed to measure undesirableoxides on metal surfaces. The technique providesquantification of oxide severity with potentially finerresolution and improved repeatability than currentlypossible. Preliminary results from the evaluation ofoxides on cold rolled aluminum samples show that oxideseverities quantified using this technique correlatewell with the discrete grades assessed by QA personnel.!3