Fatigue Crack Growth Behavior and Microstructural Mechanisms in Ti-6Al-4V Manufactured by Laser Engineered Net Shaping

Abstract

Laser engineered net shaping (LENS) is an additive manufacturing technique developed specifically for fabricating metallic materials, such as steel, titanium alloys, and nickel-based superalloys, which are widely used in critical structural components. The layering procedure, cyclic heating, and fast cooling during LENS generate unique microstructural features and mechanical properties. Numerous research studies have been conducted mainly in areas including process-related simulation, microstructure characterization, and the performance of LENS fabricated materials under static loading conditions. The fatigue and fatigue crack growth properties and mechanisms in LENS materials, however, have not been thoroughly investigated. In this study, long fatigue crack growth tests were conducted at two stress ratios (R=0.1 and 0.8), using Ti-6Al-4V fabricated by different LENS processing parameters, in both as-fabricated and heat treated conditions. Data and fundamental knowledge that facilitate the application of LENS in the design and repair of structural components were generated in this study and will be systematically discussed.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 2015
Accession Number
AD1015825

Entities

People

  • Diana A. Lados
  • Eric J. Brown
  • Gregory N. Vigilante
  • Yuwei Zhai

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Additive Manufacturing
  • Alloys
  • Electron Beam Melting
  • Fabrication
  • Fatigue Tests (Mechanics)
  • Heat Treatment
  • Manufacturing
  • Materials
  • Mechanical Properties
  • Mechanical Working
  • Mechanics
  • Resistance
  • Selective Laser Melting
  • Selective Laser Sintering
  • Tensile Properties
  • Tensile Strength
  • Titanium Alloys

Fields of Study

  • Materials science

Readers

  • Materials Science (Mechanical Engineering).
  • Nanofabrication and Microfabrication.
  • Systems Analysis and Design

Technology Areas

  • Directed Energy