Synthesis Characterization of Ni- Cr Binary Alloys Produced by Powder Metallurgy Technique

摘要

Ni-Cr (0, 0.5, 1, 4, 8, 12 wt. % Cr) alloys were prepared by mechanical alloying via powder metallurgy technique. Milling the mixed powders with powder to ball ratio 1:10 for 4 hrs, compaction under 420 Mpa and sintering at 1200 ℃ in a vacuum furnace for 1 hr. The densification was estimated by Archimedes method which confirmed that 1 wt. %Cr sample has the highest density. XRD confirmed that the formation of Ni_(2.88) Cr_(1.22) solid solution in 4%, 8% and 12 wt. %Cr samples and its peaks overlapped on the Ni peaks. Microstructure was studied by scanning electron microscope (SEM). It indicated that by addition of Cr Content the (Ni_(2.88) Cr_(1.22)) solid solution was formed and the porosity increased. Vickers microhardness of the tested samples was estimated in which 1 wt.% Cr sample recorded the highest value.