Significance of hot pressing parameters and reinforcement size on densification behavior of ZrB2–25vol% SiC UHTCs

• Published in: Ceramics international Vol. 41; no. 5; pp. 6439 - 6447
• Main Authors: Jaberi Zamharir, Mehran, Shahedi Asl, Mehdi, Pourmohammadie Vafa, Nasser, Ghassemi Kakroudi, Mahdi
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-06-2015
• Subjects: A. Hot pressing; Densification; Taguchi method; ZrB2–SiC composite; A. Hot pressing; ZrB2–SiC composite; Densification; Taguchi method
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2015.01.082

ZrB2–25vol% SiC ceramic composites were prepared by hot pressing in order to investigate the effects of processing parameters and SiC particle size (20nm, 200nm and 5µm) on the densification behavior. At this study, an experimental design technique (Taguchi method) was used to specify the significance of four factors and to obtain the optimal conditions. The statistical analysis distinguished the applied pressure as the most effective parameter on the relative density of ZrB2–SiC composites. A relative density of ~100% was obtained at the optimal processing conditions: temperature of 1850°C, holding time of 90min, pressure of 16MPa and SiC particle size of 200nm. The confirmation test, performed under optimum conditions, indicated that the experimental outcomes were equal with the expected values from the Taguchi prediction. The mechanisms of enhanced densification of hot pressed ZrB2–SiC ceramic composites were discussed.