Aluminum foil: Its typical quality problems and their causes

Thin aluminum sheets, have been extensively used as packaging and household foils to protect foods from environmental effects. As thickness of foil is reduced, the likelihood of having pinholes and strip break increases. In this study, various examples of foils, with a thickness between 7 and 75 μm and produced from twin roll cast (TRC) AA1200 coils are gathered. Causes for pinholes and strip breaks are investigated using optical, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Series of simulations are made with a laboratory scale rolling mill in order to elucidate mechanisms which lead to pinholes and strip break in foil production.