Synthesis of Nano-Sized TiB2 and TiC Particles During Spark Plasma Sintering of Ball-Milled Ti-Cu Alloy + B(C) and Ti+Cu+B mixtures

Abstract

Ti-B-Cu and Ti-C-Cu systems are interesting from the viewpoint of the development of ceramic particle-reinforced copper matrix composites. In this work, the phase and structural evolution upon the interaction of Ti33Cu67 and Ti25Cu75 alloys obtained by melt spinning with carbon or boron was studied. The reactions were carried out in the ball-milled mixtures subjected to Spark Plasma Sintering at 900 °C. The products of the reactions were composites containing TiC or TiB2 nanoparticles distributed in the copper matrix. The in-situ synthesized TiC and TiB2 nanoparticles were extremely fine (10-20 nm). The distribution pattern of the particles in the matrix was similar in the TiC-Cu and TiB2-Cu systems: composite regions were intermixed with copper regions free from the ceramic particles. It was shown that, when the Ti25Cu75 alloy was melted first by heating up to 900 °C and then forced to interact with carbon, TiC particles two orders of magnitude larger in size grew in the copper matrix.