Development of Isothermal Forging of Titanium Centrifugal Compressor Impeller

Abstract

The technology of isothermal forging of titanium has been successfully extended to the production of impeller forgings. A four-part nickel-base superalloy die set weighing approximately 2000 lb was made and used to produce ten Ti-6Al-4V alloy forgings. The ten forgings were 13 1/2 in. OD, had a plan area of 114 sq. in., weighed between 24 and 25 1/2 lb, and had 36 blades radially emanating from the hub. The blades were 0.160 in. thick at the thinnest portion and had depths ranging from 3/4 to 1/2 in. depending upon location. The thickness of the hub portion of the forging at the 13 1/2 in. OD was typically 0.210 in. Preform temperatures were typically 1750 degree F and die temperatures 1600 degree F. Press forging loads were usually 1000 tons, equivalent to 17 kpsi forging pressure. The finish-machined impeller weighs approximately 12 lb; the isothermally produced forging typically weighs 25 lb, while the forging conventionally produced for this impeller weighs approximately 60 lb. Significant savings in raw material and machining time would therefore accrue if isothermal titanium forgings are used for this part.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1973
Accession Number
AD0764266

Entities

People

  • T. Watmough

Organizations

  • IIT Research Institute

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Assembly
  • Centrifugal Compressors
  • Composite Materials
  • Compressors
  • Contracts
  • Illinois
  • Manufacturing
  • Massachusetts
  • Materials
  • Materials Laboratories
  • Mechanical Properties
  • Mechanics
  • Military Research
  • Press Forging
  • Production
  • Strain Rate
  • Titanium Alloys

Fields of Study

  • Materials science

Readers

  • Aerodynamics.
  • Electrical Engineering
  • Metallurgy