Thermodynamic stability and mechanical evaluation of YSZ-WC composite ceramics fabricated by pressureless sintering and hot pressing

초록

Yttria-stabilized zirconia (YSZ)-based engineering ceramics are manufactured by adding non-oxide additives as the typical toughening mechanism of zirconia (ZrO2). In this study, YSZ-10/20 vol% WC composite ceramics were prepared by pressureless sintering and hot pressing to view reaction pathways based on different driving forces. During the reactions, the decarburization of WC and the formation of ZrC were investigated at temper-atures of >= 1500 degrees C. W was detected at 1700 degrees C, which is related to the thermodynamic stability of various chemical reactions in the ZrO2-WC binary system. The hardness of the composite ceramics decreased, whereas the fracture toughness and wear resistance increased. The phase evaluation and reaction pathways from the thermodynamic perspective derived from the YSZ-WC binary system suggest considerable potential for the future composition designs of ZrO2-based non-oxide composite ceramics.

키워드