Effects of refractory nitride reinforcements on the microstructure, densification and microhardness of Ti6Al4V-based binary composites produced by spark plasma sintering

Autor: Olawale Popoola, A. P. I. Popoola, J. O. Abe, Emmanuel Ajenifuja
Rok vydání: 2020
Předmět:
Zdroj: IOP Conference Series: Materials Science and Engineering. 784:012001
ISSN: 1757-899X
1757-8981
DOI: 10.1088/1757-899x/784/1/012001
Popis: The effects of different refractory nitrides: aluminium nitride (AlN), titanium nitride (TiN) and hexagonal boron nitride (h-BN) reinforcements on the microstructure, densification and microhardness characteristics of spark plasma sintered Ti6Al4V-based binary composites were studied. The microstructure was examined by optical microscopy, densification was evaluated according to the method of Archimedes and the microhardness of the sintered composites was measured by Vickers microhardness tester. The SPS technique was successfully used to consolidate Ti6Al4V powder and 3 wt.% nanoparticles of AlN, TiN and h-BN respectively. The binary composites produced attained nearly full theoretical densification (98.22 to 99.54%) due to enough diffusional mass transport ensuing in solidly bonded compact of the matrix and the refractory nitride reinforcements. Ti6Al4V-3h-BN composite gave the optimal combination of relative densification and microhardness values of 99.54% and 7.03 GPa which exceeds 200% that of the monolithic alloy and about 48% superior to both composites with TiN and AlN reinforcements.
Databáze: OpenAIRE