High temperature tensile strength of large size Al2O3/ZrO2(Y2O3) directionally solidified eutectic ceramics

Abstract

Al2O3/ZrO2(Y2O3) directionally solidified eutectic ceramics (DSECs) with a diameter of 10 mm were prepared via the induction heating zone melting (IHZM) method, and Φ 5 mm cylindrical tensile specimens were processed. The effects of both Y2O3 content (1–12%) and the pulling rate (5–30 mm/h) on the tensile strength were investigated. With the increase of Y2O3 content and pulling rate, the tensile strength at 1500 °C of DSEC got the maximum of 167.1 MPa with 1% Y2O3 at 10 mm/h, and 94.3 MPa with 3% Y2O3 at 30 mm/h, respectively. Both high m-ZrO2 phase mass fraction and high intercolony area fraction are harmful to the tensile strength, while the grain refinement strengthening and whisker toughening can enhance the tensile strength.