US 4,270,380 AGranted

Metal shaping die assembly

AssigneeCorning Glass Works

InventorsSuresh T. Gulati, Henry E. Hagy

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Abstract

A die assembly comprises a steel casing shrink-fitted onto and holding a ceramic die nib for extruding, drawing, ironing and the like of ferrous and nonferrous metal stock, especially in hot workable condition. The assembly includes an interlayer between the nib and casing to accommodate imperfect dimensional mating of adjacent shrink-fitted surfaces of the nib and casing. The interlayer is composed of all-crystalline ceramic material having a heating liquidus temperature within the range of 500.degree.-570.degree. C. Rigidity of solidified interlayer maintains uniform shrink-fitted compression on nib during usage of the assembly. Nib and preferred lead-zinc-borate devitrified glass interlayer are easily, jointly removable from casing and leave casing clean for reuse without affecting its case-hardening properties.

Claims9

Dependent claims

In a die assembly for shaping metal by extrusion, drawing, ironing and the like, which comprises

a ceramic die nib having at least one aperture therein for passage of metal therethrough to work same whereby the shape and/or cross-section of the metal entering and exiting said nib is dissimilar, the nib having an outer annular surface with a coating thereon, and
steel casing means to support the nib against axial displacement in the direction of the aperture and against tensile failure in use, the casing means having an inner annular surface shrink-fitted onto and around the coated outer annular surface of the nib,
wherein the improvement comprises
the coating being composed of all-crystalline ceramic material having a heating liquidus temperature within the range of 500.degree.-570.degree. C. and which does not become softened or plastic or subject to noticeable creep when reheated in use of the die assembly for and by shaping hot metal.

1 more element

Dependencies are inferred from the claim text.