Abstract
A systematic investigation of temperature/pressure/time variables for dehydriding titanium alloy (Ti–6AI–2Sn–4Zr–6Mo) powder was made to determine practical processing conditions for reducing the hydrogen content of the powder to levels below 100 ppm. Studies made between 650·C (1200·F) and 871·C (1600·F) established the following conditions for obtaining the desired hydrogen contents:
Analyses of the experimental results of tests made between 650°C (1200°F) and 816°C (1500°F) indicate that at 1–0·088 μm partial pressure of hydrogen the dehydriding process is controlled by the second order reaction: 2H (gas)= H2 (gas) with an activation energy of 21 760 ± 1840 cal. At <0·088 μm partial pressure of hydrogen the process appears to be controlled by the rate of removal of H2 molecules clinging to the powder surfaces. The type of vacuum system used for dehydriding is believed to be the major factor governing removal of these molecules.
Notes
* Manuscript received 8 August 1974; in final form 2 December 1974.