A Metallographic Interpretation of the QLT Heat Treatment of Ferritic Cryogenic Steels.

Abstract

Commercial 5-6Ni steels are toughened for service by a 3-step heat treatment which is sometimes designated the QLT treatment. The present investigation was undertaken to determine why this treatment is necessary and successful. It was concluded that the multi-step heat treatment is necessary because of the low nickel content. The intercritical anneal (L) serves to create regions of high solute contents along the martensite lath boundaries. The intercritical temper (T) then precipitates a dense distribution of high solute, stable austenite within these enriched regions.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1982
Accession Number
ADA133428

Entities

People

  • J. I. Kim
  • J. W. Morris Jr.

Organizations

  • University of California, Berkeley

Tags

DTIC Thesaurus Topics

  • Alloys
  • Boundaries
  • California
  • Cooling
  • Ductile Brittle Transition
  • Electron Microscopy
  • Engineering
  • Heat Energy
  • Heat Treatment
  • Materials
  • Materials Science
  • Microstructure
  • Phase Transformations
  • Precipitates
  • Precipitation
  • Transition Temperature
  • Transitions

Readers

  • Powder metallurgy of Titanium alloys.