An investigation on milling rotation speed and addition time of surfactant in synthesis of Ti-Nb-Mo alloy

The influence of milling rotation speed and the addition time of a surfactant (ethylene bisstearamide; EBS) on density, hardness and surface properties of sintered Ti-10Nb-3Mo alloy (wt.%) was investigated. Six batches of powders were prepared using high-energy ball milling for 10 h. The total amount of 2 wt.% EBS was added to the powder mixture either prior to milling process or at four time intervals and each batch was run at two rotation speeds of 200 and 300 rpm. Results indicated that ball milling at 300 rpm facilitated the dissolution of solute elements throughout the Ti matrix. Furthermore, finer particles and more uniform powder distribution were obtained when EBS was added to powder mixture at four time intervals during milling process. The sintered compacts made from the ball-milled powders mixed with EBS at four time intervals exhibited higher density and hardness as well as the lowest value of surface roughness (Ra).