Sintering Behavior of Fly ash/NiCr Functionally Graded Materials Prepared by Spark Plasma Sintering (SPS)

Abstract

Fly ash/NiCr alloy functionally graded materials (FGMs) of φ 100 mm plate were prepared by spark plasma sintering (SPS). FGMs of simple stacking structure (fly ash/NiCr) and sandwich stacking structure (NiCr/fly ash/NiCr, fly ash/NiCr/fly ash) 3 to 4 mm in thickness were prepared. The deformation of simple stacked sample was caused by thermal expansion differences. The cross-section and elemental profiles of simple stacked sample were studied by scanning electron microscopy (SEM) and electron probe microanalysis (EPMA), respectively. The sandwich stacked sample of fly ash/NiCr=(100/0, 60/40, 40/60, 60/40, 100/0) had a flat shape and free of the surface crack.