Production of functionally graded SiC-TiB2-Al composites by spark plasma sintering technique and their characterization

In this thesis, the production and characterization of functionally graded SiC-TiB2-Al composites was investigated. At the begining of the study, two different designs were made with the functionally graded material approach. The composite layers of the of the designed FGMs were sintered at 1800°C for 5 minutes by using SPS (spark plasma sintering) method. Bulk density and open porosity of the composites were measured by Archiemede's method. Phase analysis was accomplished by XRD, and microstructural analysis was carried out by using SEM and/or optical microscopy. Hardness and density of produced composites was also measured. It was determined that TiB2 addition has a positive effect on sintering of SiC, and hardness of SiC-TiB2-Al composite materials. Residual porosity of the produced FGM composite materials was determined to be less than %1. In produced FGMs, hardness and fracture toughness was observed to change gradually from one surface to the other, as was aimed at.