Effect of silicon carbide addition on the microstructure, hardness and densification properties of spark plasma sintered Ni-Zn-Al alloy

Abstract

Effect of silicon carbide (SiC) additions on the physico-chemical properties of nickel-zinc-aluminium (Ni-Zn-Al) alloy prepared by spark plasma sintering technique is investigated. Elemental powder matrix samples were prepared with different amounts of SiC (1–4 wt%) and were mixed in a tubular mixer for 5 h at 49 rpm. The metal-ceramic composite powders were pressed and sintered at 850 °C with 100 °C/min heating rates, 10 min holding time and a pressure of 50 MPa. Hard disk-shaped metal matrix composite pellets (ᴓ = 40 mm, thickness = 5 mm) were obtained. Chemical, physical and microstructural properties of sintered composite samples were studied. The results show that SiC addition particles influence the physical and microstructural characteristics metal matrix composites. The samples demonstrated significant increase in relative density (83–96.53%) and hardness (132–228.36 HV) with increase in SiC additions. Compositional analysis indicated predominant nickel and silicon carbide in identified phases.