The Effect of Cold Rolling Parameters on the Densification of Titanium Sintered Strips

Abstract

Powder metallurgy (PM) is an alternative approach to ingot metallurgy (IM) in the production of metal products. It is of paramount importance for PM to be able to produce fully dense products for it to make headway in becoming an equal alternative to IM and be a better option economy-wise. Cold rolling is an inexpensive post-sintering densification option that enables the lowering of sintering conditions. Experiments were carried out in this study to investigate cold rolling parameters on the densification of titanium brown compacts with a starting relative density of 89.3 %. The highest relative density obtained during the cold rolling experiments was 97.7 % without any annealing. It was found that the density increases with an increase in the percentage reduction of cold rolling. High percentage reductions reduce the number of roll passes needed to increase the density up to a limit where the brown compacts become susceptible to severe rolling defects. It was also found that the total increase in density increases with a decrease in cold rolling speed. An increase in the relative density of 8.36 % was observed at the cold rolling speed of 1 rpm, whereas the highest increase recorded at 10 rpm was 5.83 %.