Caracteriza？？o microestrutural dos alumínios comerciais AA1100, AA1050 e AA1070 e do alumínio superpuro AA1199

a comparative study was carried out among three commercial purity aluminums with different levels of purity: aa1100 (99.00%), aa1050 (99.50%) and aa1070 (99.70%), produced on an industrial scale by direct chill (dc) process, and super pure aluminum, aa1199 (99.995%) produced in the laboratory. several techniques of microstructural analysis were used: conventional optical microscopy, scanning electron microscopy, optical microscopy with polarized light, measurements of electrical conductivity and vickers hardness. the three commercial purity aluminums showed an increase in work hardening and a decrease in electrical conductivity as the impurity content increased.