Simultaneous effect of mechanical alloying and arc-melting processes in the microstructure and hardness of an AlCoFeMoNiTi high-entropy alloy

• Published in: Journal of alloys and compounds Vol. 643; pp. S250 - S255
• Main Authors: Baldenebro-Lopez, F.J., Herrera-Ramírez, J.M., Arredondo-Rea, S.P., Gómez-Esparza, C.D., Martínez-Sánchez, R.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15-09-2015
• Subjects: Arc melting; High entropy alloys; Mechanical alloying; Microstructure; High entropy alloys; Microstructure; Mechanical alloying; Arc melting
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2014.12.059

•Multi-component systems of AlCoFeMoNiTi were produced by mechanical alloying.•Consolidated samples were fabricated by two different processing routes, sintering and arc melting.•Effect of routes of consolidation on microstructural evolution and microhardness is reported.•High hardness values are found in consolidated samples.•Alloying elements, grain size, and precipitates have a high effect on microhardness.
A nanostructured AlCoFeMoNiTi high entropy alloy was synthesized through the mechanical alloying process. Bulk samples were obtained by two different routes to compare the microstructural evolution and hardness behavior: sintering and arc melting. Through electron microscopy analyses the formation of Mo-rich and Ti-rich phases were identified in the melted sample, while Ti-rich nano-precipitates were observed in the sintered sample. A higher microhardness value was achieved on the sintered sample than for the melted sample. The disadvantage of porosity in the sintered sample in comparison to the melted one was overcome by the hardening effect produced by the mechanical alloying.