Title : Influence of the metal content on microstructure and selected properties of Al2O3-Cu-Ni composites manufactured by uniaxial pressing
This work investigated the influence of metal phase content on the microstructure and selected properties of composites from Al2O3-Cu-Ni system. The following powders were used as the initial materials: nanometric Al2O3 and micrometric metal powders: Cu and Ni. Microscopic observation indicated that the copper powder was characterized by dendritic morphology, while nickel powder had a spheroidal shape of particles with developed surface area. The composites were obtained by the uniaxial pressing. Four series with 50 vol.% of solid content and different volume of metal content with respect to the total solid volume were prepared. The metallic phase in all series contained an equal volumetric share of both metal components. Selected physical properties were determined using Archimedes method. Phase composition of sintered samples were examined by X-ray diffraction analysis. Microstructural observations were carried out with the use of Scanning Electron Microscopy. Vickers hardness and fracture toughness were specified. Physical properties revealed a high relative density of sintered composites.
Base on the obtained X-ray analysis results, it can be concluded that fabricated samples consisted of three phases: Al2O3, Ni and solid solution CuNi. The macroscopic observations indicated the homogeneous distribution of the metallic phase in the ceramic matrix in obtained samples. Conducted mechanical properties analysis showed that an increase of metal content in the composite results with a decrease of its hardness with simultaneous increase of fracture toughness. Based on the conducted research it was concluded that uniaxial pressing allows to obtain composites from the ternary Al2O3-Cu-Ni system. The experimental results indicate the amount of metallic phase in the composite has a significant impact on its properties and microstructure. The results of the study could help to understand and design a more effective process of production of composites from Al2O3-Cu-Ni system.
The study was accomplished thanks to the funds allotted by The National Science Centre (Poland) within the framework of the research project ‘OPUS 13’ no. 2017/25/B/ST8/02036. This investigation supported by the Foundation for Polish Science (FNP).
• This paper describes a preliminary investigation on the composites from the ternary Al2O3-Cu-Ni system manufactured by uniaxial pressing. The studies carried out included description of the influence of metallic phase content on the final microstructure and properties of composite material. We believe that these results of the study could help to understand and design a more effective manufacturing process of composites from Al2O3-Cu-Ni system.