Effects of 2D Ti3C2TX (Mxene) on mechanical properties of ZK61 alloy

Highlights: • Most of the Ti₃C₂T_X remained the complete structure and had a uniform distribution in the grain boundary. • The Ti₃C₂T_X showed a relatively high strengthening efficiency and a similar performance as graphene. • The Ti₃C₂T_X was surrounded by the in-situ synthesized MgO nanoparticles, which distributed disorderly in the interface and enhanced the interfacial bonding. -- Abstract: Two-dimensional Ti₃C₂T_X (Mxene) is a new attractive reinforcement in composites due to its high aspect ratio and rich surface functional groups, but in metal matrix composites the enhancement of Ti₃C₂T_X is far from expectation, which is due to its poor thermal stability and oxidation resistance. To reveal the performance of Ti₃C₂T_X in magnesium matrix composites, ZK61 alloys reinforced with Ti₃C₂T_X are fabricated by spark plasma sintering, which are conducted at low sintering temperatures with a relatively short sintering time to maintain the stability of Ti₃C₂T_X. With 0.5 wt% Ti₃C₂T_X, the hardness increased by 5.4%, the compressive yield strength (CYS) increased by 28.7% and the failure strain decreased by 6.1%. The Ti₃C₂T_X shows a relatively high strengthening efficiency and a similar performance as graphene. The Ti₃C₂T_X distributes uniformly in the grain boundary and is surrounded by the in-situ synthesized MgO nanoparticles, which distribute disorderly in the interface between the Ti₃C₂T_X and the α-Mg matrix. When the Ti₃C₂T_X content increases to 1.0 wt%, the hardness and CYS increased further, but the failure strain decreased by 70.7%. The Ti₃C₂T_X clusters and thicker grain boundary resulted in the grain boundary embrittlement and induced the intergranular fracture, which resulted in the decrease of the strain hardening and uniform elongation.