The tensile behaviour and the creep behaviour of SCS-6/Ti-6Al-4V composites in the transverse direction at 482#xB0;C were evaluated. The tensile strength of the transverse composite was 360 MPa; the unreinforced matrix strength was more than 600 MPa. Separation of the fibre-matrix interface was the primary cause for the transverse composite's low tensile strength. Creep tests were performed in air at 482#xB0;C over the stress range of 69 to 276 MPa. The composite was less creep-resistant than the matrix when tested at stress values higher than 150 MPa. Below 150 MPa, the creep-resistance of the composite and the unreinforced matrix were very similar. Finite element analyses were performed for a composite with an infinite, periodic, uniform fibre array and two different fibre-matrix interface strength assumptions. Two matrix material models were used: isotropic plasticity with steady-state creep, and the #x2018;viscoplasticity based on overstress#x2019; unified theory. Both material models were able to represent the stress-strain and steady-state creep behaviour of the matrix. The composite's tensile behaviour was best approximated by a model with no strength at the fibre-matrix interface. The composite's measured minimum creep rates were between the predictions made with a perfectly bonded interface and an interface with no strength. The comparison of the predictions with the creep data suggested that the fibre-matrix interface possessed a finite amount of bond strength and that a certain fraction of these interfaces remains bonded during creep deformation.
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