Influence of High-Energy Milling and Sintering Cycle on Obtaining TiAl from Elemental Ti and Al Powders

The present work studies the influence of high-energy milling (HEM) and sintering cycle of Ti and Al powders on the obtainment of TiAl. This study shows that HEM modifies the diffusion processes during the sintering stage. The ignition temperature of the exothermic reaction (SHS) that occurs between Ti and Al, was considered as the key parameter of the sintering process, leading to the study of sintering cycles that avoid uncontrolled processes caused by the SHS reaction. The samples were obtained by cold uniaxial and isostatic pressing, pre-sintered at different temperatures, and then heated up to the sintering temperature. This study also shows the effect of powder additions processed by HEM on the sintering behavior of blended elemental Ti and Al powder compacts.

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