Tensile Properties and Microstructures of Laser-Formed Ti-6Al-4V

  • J. Alcisto
  • A. Enriquez
  • H. Garcia
  • S. Hinkson
  • T. Steelman
  • E. Silverman
  • P. Valdovino
  • H. Gigerenzer
  • J. Foyos
  • J. Ogren
  • J. Dorey
  • K. Karg
  • T. McDonald
  • O. S. Es-Said
Article

Abstract

The room temperature tensile properties of Ti-6Al-4V alloy prepared under two different processing routes were evaluated and compared. One group of samples was prepared by conventional casting-forging-rolling into flat plates. The other group was prepared by using Triton’s Laser Free-Form Fabrication (LF3)™ processes, i.e., a laser was used to melt pre-alloyed powders of the required metallic composition as they were dropped onto a moveable substrate programmed to move in such a manner as to form a solid alloy plate. Five populations of Ti-6Al-4V were evaluated: a standard wrought form, an as-deposited form, a machined as-deposited form, a heat-treated as-deposited form, and a machined as-deposited and heat-treated form. The poorest mechanical properties occurred with the rough surfaces, likely due to existing microcracks and stress concentrations. The LF3™ as-deposited material had mechanical properties comparable to, if not higher than, the mechanical properties of the wrought material. Further evaluations of the laser-formed material for complex spacecraft piece parts were warranted, specifically in regards to improving the surface finish of the materials.

Keywords

laser free-form fabrication (LF3) mechanical properties microstructure Ti-6Al-4V 

Notes

Acknowledgments

The authors wish to acknowledge the financial support for this project from the National Science Foundation, Grant No. EEC 0097863. They also wish to thank Ms. Jaisey Simard and Mr. Roman Silva for preparing the manuscript.

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Copyright information

© ASM International 2010

Authors and Affiliations

  • J. Alcisto
    • 1
  • A. Enriquez
    • 1
  • H. Garcia
    • 1
  • S. Hinkson
    • 1
  • T. Steelman
    • 2
  • E. Silverman
    • 2
  • P. Valdovino
    • 2
  • H. Gigerenzer
    • 3
  • J. Foyos
    • 1
  • J. Ogren
    • 1
  • J. Dorey
    • 1
  • K. Karg
    • 3
  • T. McDonald
    • 3
  • O. S. Es-Said
    • 1
  1. 1.Mechanical Engineering DepartmentLoyola Marymount UniversityLos AngelesUSA
  2. 2.Northrop Grumman, Space TechnologyRedondo BeachUSA
  3. 3.Triton Systems IncorporatedChelmsfordUSA

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