Abstract
This paper investigated the die-pressing and sintering behavior of the low-cost CP-Ti and Ti-6Al-
4V powders made by the Armstrong Process®. The Armstrong powders have an irregular coral
like, dendritic morphology, with a dendrite size of approximately 2-5 m. As-received as well as
milled powders were uniaxially pressed at designated pressures up to 690 MPa to form disk
samples with different aspect ratios. In the studied pressure range, an empirical powder compaction
equation was applied to linearize the green density – pressure relationship, and powder compaction
parameters were obtained. The Armstrong Ti-64 powder exhibited a significantly higher
sinterability than the CP-Ti powder. This was explained to be due to the higher diffusivity of V at
the sintering temperature. The Ti-64 samples with a green density of 71.0% increased to 99.6%
after sintering at 1300oC for 1 hour. An ex-situ technique was used to track the powder morphology
change before and after sintering.
