Patent ID: 6491865
Filing Date: 2002-12-10
Classification: C21D

Abstract:
Fixture apparatus for supporting at least one thin, planar sheet metal work piece fabricated of heat treat hardenable alloy during a heat treat cycle wherein the work piece is immersed in a first bath of liquid heating medium for heating the work piece to an elevated temperature followed by immersion in at least one bath of liquid cooling medium to quickly lower the temperature of the work piece to effect heat treat hardening of the work piece, said fixture apparatus comprising:at least a pair of rigid support walls having oppositely disposed inner support surfaces that are substantially planar to define an envelope therebetween for the accommodation of at least one of such parts between said walls, said walls being coupled in such manner as to engage opposite sides of the work piece with said inner support surfaces in such manner as to support the work piece against movement out of its plane while permitting unrestricted movement of the work piece within its plane during the heat treat cycle; said walls being substantially porous to permit the free flow of the liquid heating and cooling medium through said walls for intimate contact with the work piece to achieve rapid uniform heating and cooling of the work piece, with the porosity being generally uniform across said support surfaces of said walls; wherein said pair of opposing support walls comprise a pair of inner porous panels backed by at least one pair of outer porous panels; and said outer panels comprise generally coarse open mesh screening having relatively large pore openings providing a rigid supportive exoskeleton for said inner panels, and said inner panels comprising relatively finer open mesh screening having relatively smaller pore openings.