Materials Research Bulletin, Vol.31, No.4, 397-404, 1996
Electrical and Mechanical-Properties of ZrO2(2 Mol-Percent Y2O3)/WSi2 Composites and Thetr Laminated Materials
Well-densified composites with the compositions ZrO2(2Y)/WSi2 = 60/40 and 80/20 mol% have been fabricated by hot isostatic pressing for 2 h at 1500 degrees C and 196 MPa. Electric resistivities (rho) of the two composites are very different; the former and latter composites correspond to metallic and insulating materials, respectively. The properties are strongly dependent on the textures. Laminated materials with the ZrO2(2Y)/WSi2 = (60/40)/(80/20)/(60/40) mol% have been prepared by the same technique. Overall electric resistivities in directions perpendicular and parallel to the interfaces have been determined to be rho(perpendicular to) approximate to 1x10(11) Omega . cm and rho(parallel to) approximate to 1x10(-4) Omega . cm, respectively. Residual stress as much as approximate to 150 MPa is induced in the interfaces. The fracture toughness (K-Ic) is greatly affected by the residual stress.
Keywords:FRACTURE-TOUGHNESS;INDENTATION