Laminated structure optimization and drawing performance of Al2O3–TiC/Al2O3–TiC–CaF2 self-lubricating laminated ceramic conical die

Abstract

In the present study, Al2O3–TiC/Al2O3–TiC–CaF2 self-lubricating laminated ceramic conical dies were fabricated. Experiments were carried out to obtain values of hardness and fracture toughness of the conical dies for different laminated numbers and laminated thickness ratios. Drawing experiments were also conducted by a universal tensile testing machine. The worn surfaces were observed by a Scanning Electron Microscope (SEM) and Energy Dispersion Spectrum (EDS) to analyze the wear mechanisms and self-lubricating effect. Results show that the Al2O3–TiC/Al2O3–TiC–CaF2 self-lubricating laminated ceramic conical dies possess compact structure and well-bonding interface between layers. When the laminated number is 5 and laminated thickness ratio is 1:1, Al2O3–TiC/Al2O3–TiC–CaF2 self-lubricating laminated ceramic conical die reveals the best mechanical properties with the Vickers hardness and fracture toughness of 18.3±0.3GPa and 5.7±0.2MPam1/2 respectively. In addition, the drawing force decreases with an increase of drawing speed and drawing displacement under no lubrication condition. The wear mechanisms of Al2O3–TiC–CaF2 composites layer and Al2O3–TiC composites layer are mainly abrasive wear and adhesive wear. The conical dies׳ self-lubricating capacity has been generated by the ‘dragging effect’ during drawing process.