Processing, Microstructure, and Tensile Properties of the Ti-6Al-4V-1.55B Eutectic Alloy (Preprint)

Abstract

Boron addition to conventional titanium (Ti) alloys instigates precipitation of intermetallic TiB whiskers that provide significant increases in strength and stiffness. The eutectic composition is the maximum boron concentration that provides these benefits via melt processing while maintaining reasonable ductility and damage tolerance. The eutectic point for the most widely used Ti alloy, Ti-6Al-4V (weight percent), modified by B addition, was determined to occur at 1.55+0.05B and 1545+5 ?C. The microstructure, texture, and tensile properties of the eutectic alloy are sensitive to ingot solidification conditions and melt pool morphology. Several microstructural forms in the as-cast condition as well as their transformation during thermomechanical processing (TMP) were identified. Two types of eutectic structures, aligned and random, were obtained. Cast microstructures with random eutectic colony orientation had no marked crystallographic texture, while cast aligned microstructure had a strong [020] texture for the TiB phase and a <110> circular texture for the alpha-Ti phase.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 2007
Accession Number
ADA467919

Entities

People

  • Daniel B. Miracle
  • Orest Ivasishin
  • Roman V. Teliovych
  • Seshacharyulu Tamirisakandala
  • Volodymyr G. Ivanchenko

Organizations

  • Air Force Research Laboratory

Tags

Communities of Interest

  • Space

DTIC Thesaurus Topics

  • Air Force Research Laboratories
  • Damage Tolerance
  • Ductility
  • Heat Energy
  • Materials
  • Mechanical Properties
  • Mechanical Working
  • Microstructure
  • Modulus Of Elasticity
  • Orientation (Direction)
  • Precipitation
  • Shape
  • Stiffness
  • Temperature Gradients
  • Tensile Properties
  • Tensile Strength
  • Titanium

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Metallurgy