Growth and characterization of Al2O3/Y3Al5O12/ZrO2 ternary eutectic fibers

Al2O3/Y3Al5O12/ZrO2 ternary eutectic fibers have been grown for the first time by the micro-pulling-down method and their microstructural and mechanical properties investigated as a function of solidification rate. Al2O3/Y3Al5O12/ ZrO2 ternary eutectic fibers 0.3-2 mm in diameter and 500mm in length have been grown with a putting rate of 0.1-15mm/min. The ternary eutectic fibers had homogeneous and regular 'chinese script-like' microstructures. The interlamellar spacing;. exhibited an inverse-square-root dependence on the pulling rate nu according to lambda = 8 x nu (- 1 2), where A has the dimension of m and nu is in mum/s. The hardness reached 17.4 GPa for fibers grown at a pulling rate of 15 mm/min, and the tensile strength was measured to be 1100 MPa at 25 degreesC and 970 MPa at 1200 degreesC for a fiber grown at a pulling rate of 15 mm/min. The hardness increased as the interlamellar spacing decreased. (C) 2001 Elsevier Science B.V. All rights reserved.