Magna International Inc.
METHOD AND SYSTEM FOR USING AIR GAPS IN HOT-STAMPING TOOLS TO FORM TAILOR TEMPERED PROPERTIES

Abstract:

A sheet metal blank is hot-stamped between first and second tool surfaces of first and second die tools, respectively, to form a hot-stamped product. That product is then heat treated between the first and second tool surfaces. An actively cooled portion of the tool surfaces quenches part of the hot-stamped product to form a hardened zone. An actively heated portion of the tool surfaces slows heat transfer from the hot-stamped product to the heated portion, which causes the hot-stamped product to have a soft zone. A matrix of insulating gaps is formed in the heated portion to further slow the rate of heat transfer from the hot-stamped product to the heated portion. The insulating gaps may facilitate the use of a lower-temperature heated portion, which may consequently save energy and result in the heated portion having greater wear resistance and longer life.