The Fabrication and Characterization of a TiB2/Ni Composite Using Spark Plasma Sintering

Ni matrix composites synergistically reinforced by TiB2 particles were prepared by spark plasma sintering. According to the Nelsone Riley method and Debye-Scherrer formula, the driving force for the growth of crystallite in sintered TiB2/Ni composites was discussed by using X-ray diffraction technique to analyse the dislocation density and lattice strain of composite powders. TiB2/Ni composites not only showed great increase in tensile strength but also possessed perfect ductility. Tensile results showed that Ni-3TiB(2) (3vol% TiB2) showed an increase in tensile strength, furthermore, contained an acceptable elongation of 45%. Besides, the strengthening mechanism was discussed later. The corrosion resistance test of TiB2/Ni composites was performed by electrochemical method in 3.5wt% NaCl solution. Results showed that the corrosion resistance of pure Ni sample was superior to that of other specimens. SEM of tensile fracture revealed that debonding phenomenon between TiB2 and Ni was hindered.