First-principles study on selective laser melting of Ti48Al2Cr2Nb alloy

Abstract

The Ti48Al2Cr2Nb alloy formed by selective laser melting (SLM) was simulated by first-principles. The crystal phase relationship and interface bonding mechanism between the basic phases α₂-Ti₃Al and γ-TiAl in the alloy were simulated, and the interface stability of the Ti48Al2Cr2Nb alloy structure was explored. The results show that the Ti center-ST model in the γ-TiAl(111)/α₂-Ti₃Al(0001) interface model has the largest interfacial bonding work, the smallest interfacial energy and the strongest interfacial stability. The Cr and Nb elements are doped in the α₂-Ti₃Al(0001)/γ-TiAl(111) interface system, the bonding work and segregation enthalpy of the interface under the four doping systems were compared. It was found that the interface model doped with Cr and Nb was beneficial to improve the bonding strength of the interface and was beneficial to the stability of the interface.