Patent Number: 6,168,754

Title: Method and apparatus for densifying powder metal preforms

Abstract: A multi-stage forming tool for densifying the outer perimeter of post-sintered powder metal preforms includes a series of axially spaced die plates having different sized die openings arranged from largest to smallest. An oversized powder metal preform it is forced by a punch through the successive die openings causing the outer perimeter material to be displaced and densified. The space between successive dies allows for elastic recovery of the preform to maximize the compressive stress imparted to the preform at each die stage. A high density, high strength powder metal component results which is suitable as a replacement for wrought components in high strength applications such as transmission gears.

Inventors: Woolf; Richard Mark (Cincinnati, OH), Riley; Eric (Troy, OH)

Assignee: Federal-Mogul World Wide, Inc.

International Classification: B22F 5/08 (20060101); B22F 3/12 (20060101); B22F 3/03 (20060101); B22F 3/20 (20060101); B22F 3/16 (20060101); B22F 003/24 ()

Expiration Date: 01/02/2018