EFFECT OF PROCESSING PARAMETERS ON THE EARING AND MECHANICAL-PROPERTIES OF STRIP CAST TYPE-3004 AL-ALLOY

Electrical resistivity, superficial hardness, tensile testing, and qua ntitative metallography techniques were used in this study. The strip cast type 3004 aluminum alloy received sixteen different thermomechani cal treatments before cups were drawn. The top edges of the drawn cups were not flat. Rather, there were high points or ears with valleys be tween them. The homogenization temperature varied from 510 to 621-degr ees-C at 24 h. Some samples received an additional 426-degrees-C/24 h homogenization anneal. Most specimens were rolled along the longitudin al direction of the as-cast material, and some were rolled in the tran sverse direction. Most samples were recrystallized at 454-degrees-C fo r 24 h in addition to the homogenization treatment. Some were recrysta llized for 168 h. All samples were subsequently rolled to 0.33 mm for cup drawing and percent earing determination. The percent earing resul ts of some samples were less than 1.5%, but the mechanical strength wa s also lowered. The high-temperature recrystallization anneal of 454-d egrees-C was the controlling factor in determining the earing and mech anical strength of the final rolled sheet.