Effects of manganese on diffusion and wear behavior of ZTA particles reinforced iron matrix composites in vacuum

Abstract

Different volume fraction ZTA particles reinforced high chromium cast iron (HCCI) matrix composites were fabricated by liquid phase sintering (LPS) in vacuum of −0.1 atmospheric pressure. The influence of manganese on the microstructure, phase constituents and mechanical properties of the ZTA particles reinforced HCCI composites was investigated by means of SEM, XRD, and nanoindentation tests. The results demonstrated that the interfacial layer with a thickness of 25–35 μm was formed between ZTA particles and HCCI matrix, combined the effects of manganese additions. The elements in the interfaces layer are mainly Mn, Si, Zr and Al with a small amount of Fe. New phases formed by MnO acting on the surface of ZTA particles and the interfaces were MnO2·Al2O3, Mn2SiO4 and MnFe2O4. However, in the interfaces layer near the matrix, MnO was reduced by C to form Mn and Mn3C and dissolved in HCCI matrix. The hardness and modulus of the interfacial layer were 20.25 GPa and 294.7 GPa, respectively. The wear mass losses of Cr20 sample is about 4.7 times higher than that of 40 vol% ZTA particles reinforced iron matrix composites.