Investigation of Martensite α’ Phase Transformation During Heat Treatment of High-Speed Selective Laser Melted Ti6Al4V Components

  • P. M. LekoadiEmail author
  • N. Maledi
  • M. Tlotleng
  • B. N. Masina
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


This study presents the investigation of microstructural and hardness properties of high-speed selective laser melted (SLM) produced Ti6Al4V coupons after various heat treatments. Heat treatment was performed in order to homogenize and improve the microstructure of the as-built Ti6Al4V by transforming the acicular martensitic α’ phase. Optimized heat treatment parameters were selected based on their impact on the transformation of the acicular martensite α’ phase and the phase morphology produced after heat treatment. It was found that sub-transus heat treatments do not completely transform the martensite α’ phase, but result in the decrease in hardness. Heat treatment at 1000 °C, for 2 h followed by furnace cooling, transformed the martensitic α’ phase into a lamella α + β phase. A relationship of hardness, as a function of heat treatment temperature, is also reported.


Heat treatment Ti6Al4V Martensite 


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Copyright information

© The Minerals, Metals & Materials Society 2020

Authors and Affiliations

  • P. M. Lekoadi
    • 1
    Email author
  • N. Maledi
    • 2
  • M. Tlotleng
    • 1
    • 3
  • B. N. Masina
    • 1
  1. 1.CSIR National Laser Centre, Laser Enabled Manufacturing GroupPretoriaSouth Africa
  2. 2.School of Chemical & Metallurgical EngineeringUniversity of the WitwatersrandJohannesburgSouth Africa
  3. 3.Department of Mechanical Engineering ScienceUniversity of JohannesburgJohannesburgSouth Africa

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