Powder Metallurgy Ti-6Al-4V Alloy with Wrought-Like Microstructure and Mechanical Properties by Hydrogen Sintering Academic Article uri icon

abstract

  • Hydrogen sintering phase transformation (HSPT) is a low-cost, blended elemental, press and sinter powder metallurgy process. During HSPT, compacts of TiH2 powder are sintered in dynamically controlled partial pressures of hydrogen followed by a vacuum anneal (dehydrogenation). The use of hydrogen in the sintering atmosphere allows phase transformations in the Ti – H system to create an ultra-fine lamellar microstructure in the as-sintered state with mechanical properties that exceed ASTM standards. Additionally, the fine lamellar structure allows for secondary heat treatments to produce wrought-like microstructures. The removal of hydrogen in the dehydrogenation step is critical to prevent hydrogen embrittlement. The kinetics of dehydrogenation are discussed, in which a model for the concentration profile and an empirical equation for maximum hydrogen concentration as a function of time and size are developed.

published proceedings

  • Key Engineering Materials

author list (cited authors)

  • Dunstan, M., Fang, Z. Z., Koopman, M., & Paramore, J

citation count

  • 3

complete list of authors

  • Dunstan, Matt||Fang, Z Zak||Koopman, Mark||Paramore, James

publication date

  • August 2016