Results of high-energy ball milling of Ti and Fe powder mixtures to obtain TiFe intermetallic compound are reported. Previously, we used various process control agents (PCAs) to solve a cold welding problem in a SPEX mill. In this work, we continue that investigation but without adding PCAs and also using a planetary ball mill. Four different strategies were tried to avoid or minimize cold welding: (a) preliminary milling of a small quantity of the mixture, dirtying the vial walls and the balls surfaces before milling the main charge, (b) stepwise milling with the rotation and the inversion of the vial between the steps (only in SPEX), (c) milling Ti and Fe powders (apart from each other) before milling the mixture of them, and (d) finally milling Fe powder with Ti hydride powder. The loose powder mass and the crystalline phases formed (identified by XRD analysis) after milling were used to compare the procedures. High loose powder yields could be attained but with no major TiFe formation.
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