Microstructural and Mechanical Properties of Er_2O_3-ZrO_2 Ceramics with Different Er_2O_3 Contents

摘要

In this study, the effect of erbium oxide (Er_2O_3) addition on the microstructure, sinterability and mechanical properties of cubic zirconia (c-ZrO_2) was investigated. 0-15 wt% Er_2O_3 and c-ZrO_2 powders were mixed by means of colloidal processing and the specimens were sintered at different temperatures for 1 hour. The XRD results showed the existence of cubic crystal structure in all specimens. The lattice parameter of the specimens decreased with increasing Er_2O_3 addition up to 10 wt% and remained unchanged after this amount. The grain size of the Er_2O_3 doped c-ZrO_2 specimens dropped up to 5 wt% Er_2O_3 addition and stayed almost unchanged at higher Er_2O_3 contents. Both hardness and fracture toughness measurements were done using Vickers hardness tester. The fracture toughness values of the undoped, 1, 5, 10 and 15 wt% Er_2O_3 doped c-ZrO_2specimens were found to be 1.64 MPam~(1/2), 1.77 MPam~(1/2), 2.06 MPam~(1/2), 2.57 MPam~(1/2) and 2.31 MPam~(1/2) respectively.