Properties of Powder Metallurgy Steel Forgings

Abstract

The effects of processing variables on the mechanical properties of heat-treated powder metallurgy (P/M) steel forgings were determined. Three powders, AISI 4650 and modified AISI 4600 powders blended with graphite to yield 4640 composition, and AISI 4650 powder, were compacted into preforms and hot forged in a warm, closed die. Variables studied were preform density, method of lubrication, preform sintering (time, temperature and atmosphere), forging pressure (20 and 40 tsi) and temperature (1850F, 2000F and 2200F), and forging ratio (0.85 and 0.95). Relationships between interconnected porosity and total porosity for the various preform densities were determined. High density compacts required higher sintering temperatures due to the restricted mobility of the reducing gases in the pores. Die wall lubrication was comparable to admixed lubrication, and it simplified powder mixing and preform sintering operations.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1976
Accession Number
ADA031811

Entities

People

  • Andrew Crowson
  • Ferrel E. Anderson
  • Richard J. Grandzol

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Ductility
  • Grain Size
  • Graphitic Materials
  • High Density
  • Materials
  • Mechanical Properties
  • Mechanical Working
  • Mechanics
  • Metallurgy
  • Particles
  • Powder Metallurgy
  • Powder Metals
  • Reduction Of Area
  • Tensile Properties
  • Tensile Strength
  • Test And Evaluation
  • Yield Strength

Fields of Study

  • Materials science

Readers

  • Metallurgy
  • Powder metallurgy of Titanium alloys.