Towards strength-ductility synergy in nanosheets strengthened titanium matrix composites through laser power bed fusion of MXene/Ti composite powder

A Ti3C2 MXene/Ti composite powder was developed through surface modification and powder coating for producing a high-performance titanium matrix composites (TMCs) by laser power bed fusion. Introducing MXene rarely changed the original sphericity and flowability of Ti powder while it slightly enhanced the laser absorption capacity of Ti powder. The printing conditions in turn affected the morphology and distribution of MXene in as-printed composites. At optimised printing parameters, majority of MXene with high structural integrity and uniform distribution remained along the grain boundaries of as-printed composites, and a combination of high surface quality, geometrical accuracy and densification was obtained. The remaining MXene played the synergy of pulling-out effect and load transfer role, which increased the yield strength from 530 to 710 MPa, while retaining good ductility (elongation of 19.8%). Compared with ASTM standard cast Ti64 alloy, our MXene/Ti composites also exhibited superior comprehensive tensile properties and excellent strength-ductility synergy.

Automated summary

A Ti3C2 MXene/Ti composite powder was developed for producing high-performance titanium matrix composites (TMCs) by laser 3D printing. Introducing MXene slightly enhanced the laser absorption capacity of Ti powder without changing its original sphericity and flowability. The printing conditions affected the morphology and distribution of MXene in the as-printed composites. At optimized printing parameters, MXene remained along the grain boundaries of the composites, resulting in high surface quality, geometrical accuracy, and densification. The synergy of pull-out effect and load transfer from the remaining MXene increased the yield strength and retained good ductility.