VERFAHREN ZUR HERSTELLUNG MONOLITHISCHER ALUMINIUMSTRUKTUREN

摘要

A method for forming monolithic structures from a plurality of aluminum or aluminum alloy sheets is provided which integrates a method for producing a selective fine grain structure in each of the sheets, with roll bonding and superplastic forming. The sheets are subjected to isothermal aging or controlled slow cooling to obtain a desired grain size in each of the respective sheets. Different heating and cooling treatments can be individually applied to each of the sheets so that the sheets can be tailored to have a fine grain or a coarser grain. Stop-off material is applied at selected areas of the sheets, and the resulting stack of sheets is subjected to cold roll bonding to bond adjacent surfaces of the sheets where stop-off material has not been applied. The roll bonding step also serves to plastically deform the sheets. The roll-bonded stack of sheets is then subjected to rapid heating for recrystallization of one or more of the sheets into a fine grain structure. After recrystallization, the sheets are subjected to superplastic forming into the desired monolithic structure.