Preparation, microstructure and tensile properties of two dimensional MXene reinforced copper matrix composites

Abstract

The dispersion homogeneity of particles has a significant influence on the mechanical properties of particle reinforced metal matrix composites. In this study, a new Cu matrix composites with uniform dispersion of submicron and nanoscale MXene reinforcement particles were fabricated by the methods of high energy ball milling and hot pressing sintering. The microstructure evolution of MXene-Cu composite powders were studied in detail. When the initial MXene content is less than 3 vol%, the MXene particles can be dispersed homogenously in Cu matrix after 12 h ball milling. The refinement and dispersion of the MXene particles are mainly achieved by the cold welding and plastic deformation of composite particles in ball milling process. The XRD and TEM results reveal that these MXene reinforcement particles have been transformed to cubic TiC x in the final MXene/Cu composites. The tensile test results indicate that the UTS and elongation of the MXene/Cu composites are closely related to the dispersion homogeneity of the MXene particles. The UTS and elongation of the 1MXene/Cu and 3MXene/Cu composites increase with increasing the ball milling time. The UTS of the 3MXene/Cu-12 h can reach to 314 MPa with an elongation of 11.1%. The maximum UTS of the 5MXene/Cu-6 h can reach to 354 MPa. However, further increase in milling time would result in the UTS and elongation decline. The fracture surface analysis further testifies that the 3MXene/Cu-12 h composite presents a typical plastic fracture feature, while the 5MXene/Cu composite with various ball milling time all present brittle fracture characteristic for the severe agglomeration of MXene particles.