Investigating the Effect of Microstructure on Oxidation Behavior of Ti47Al48Mn5 Alloy Synthesized by Mechanical Alloying

The aim of this investigation was to produce Ti47Al48Mn5 intermetallic compounds with different microstructures in order to study their oxidation behavior. The reason for selecting manganese as an alloying element was to enhance the toughness of the compound. Ti47Al48Mn5 alloys were obtained through mechanical alloying، cold pressing and heat treatment. XRD results showed that milling of the elemental powder mixture for 30 hours causes the formation of Al and Mn in Ti solid solution، while by increasing milling time up to 50 hours، amorphization of powder mixture occurs. To obtain duplex and fully lamellar microstructures، the mechanically alloyed powders were cold pressed and then heat treated at 1100 °C and 1400 °C in argon atmosphere for 50 hours، respectively. The results of the oxidation test at 1000 °C revealed that the different microstructures of Ti47Al48Mn5 alloy investigated in this study have little effect on the oxidation resistance، and similar oxidation mechanisms existed for the two microstructures.