HOT UPSETTING OF POROUS ALLOY-STEEL PREFORMS

Abstract

The thermoviscoplastic response and the densification behaviour of porous alloy steel preforms under hot upsetting conditions are investigated at various temperatures and strain rates. A higher density can be attained by hot upsetting if a higher density preform is used at a temperature above 900-degrees-C. Relative density and plastic volume strain relationships are dependent on initial relative density but not on the testing temperature. The density distributions of upset specimens are found by using the relationship between Rockwell hardness and relative density for sintered porous alloy steel. These density distributions are compared with results from image analysis. (C) 1993 The Institute of Materials.