Nanoindentation and microstructure of interfacial layer in Ni-NiTi coated zirconia toughened alumina particles reinforced high chromium cast iron matrix composites

Abstract

The Ni-NiTi coated zirconia toughened alumina particles (ZTAp@Ni-NiTi) are prepared by electroless Ni plating and NiTi electroplating in succession. And the ZTAp@Ni-NiTi reinforced high chromium cast iron matrix composites (ZTAp@Ni-NiTi/HCCI) with tight interfacial bonding are produced by nonpressure casting infiltration. X-Ray Diffraction results show that an interface layer, containing new phases of Ti2O3, TiO, Ni3Ti, NiTi2, NiTi and FeCrNi, is formed between the HCCI matrix and ZTA particles. The hardness and Young’s modulus of the interfacial layer in ZTAp@Ni-NiTi/HCCI are 5.691 GPa and 224.707 GPa, respectively. Compared to ZTA particles reinforced high chromium cast iron matrix composites, a high modulus of the interface layer can effectively ease the unevenness of plastic deformation in ZTA reinforcement and HCCI matrix, exhibiting an excellent comprehensive nanomechanical property.