THE MOST ADVANTAGEOUS CONDITIONS FOR EXTRUDING AlMgSi ALLOYS WITH SOLUTION HEAT TREATMENT AT THE PRESS OUTPUT

摘要

An effect of the cooling rate on the conditions of extruding products from the AlMgSi (6063) billets after homogenization, T5 in temper, was investigated. First of all, possibility of obtaining the most advantageous microstructure of the billets was analyzed. Samples were taken from industrial billets, which were homogenized at 580 deg C and then cooled at different rates. Eight different cooling rates were used, ranging from 24 deg C/h to water cooling (42 500 deg C/h). It was found that at the cooling rates over 300 deg C/h it was possible to obtain very fine particles of a Mg_2Si phase, below 1 mu m in size.