METHOD OF APPLYING MARKING AGENT TO ALUMINUM SHEET FOR SCRAPSORTING PURPOSES

摘要

Application of a marking agent to metal stock, such as aluminum sheet, durin g and as a part of procedures for preparing the sheet for subsequent, scrap- generating manufacturing operations, to provide a detectable mark on pieces of manufacturing scrap derived from the marked sheet and commingled with scrap of other aluminum alloy sheet, so that the scrap can be sorted and the marked alloy scrap pieces separated from scrap of other alloy sheet to which the marking agent was not applied. Different marking agents, providing detectabl y different marks, may be respectively applied to sheet of different compositions if scrap pieces of more than two different compositions or compositional families are to be sorted and separated from each other. The marking agent may be added to a lubricant or prelubricant conventionally applied to the sheet by the sheet producer prior to delivery to the manufacturing customer. If an indelible marking is applied selectively only to areas of the sheet stock that will be scrapped, it can be safely retained throughout the manufacturing operation without affecting the final produced article.