P.W.M. Peters et al. / Journal of the European Ceramic Society 20(2000)531-535 Vp=0.159, respectively. The density of the plate reached Parallel sided specimens with a width of 10 mm as 3.0015 g/cm3. Dog-bone type specimens were cut from indicated in Table 3 were also cut from the plates but he plate in 00-direction by waterjet. For a first test ser- now with the aid of a diamond wire machine. Specimens ies waisting of the specimens from a width of 15 mm in cut under an angle of 45 with respect of the 0-direc the grip range to a 10 mm wide gauge section was per- tion are used to measure the shear modulus g and the formed according to the dimensions in Fig 3 and Table intralaminar shear strength at room temperature. Fur- 1. As most of the specimens tested in the first test series ther 10 mm wide specimens were cut transverse to the broke near the radius the shape of the specimen was 0%-direction. After this these specimens were ground adapted to give a smoother change of width. The x-y with a diamond wheel on both surfaces in order to coordinates for the changed specimen shape is given in remove the surface layers so that finally specimens with Table 2 the orientation 900.2/02/900.2 remain. The stiffness of the The dog-bone specimens were loaded up to failure in crossply specimens with two different relative amounts a tensile test performed at different temperatures of transverse plies (Voe=50% and V9oe=16.6% between room temperature and 1200.C as a respectively) allows the determination of the moduli of In order to Itee a homogeneous temperature dis- the parallel and transverse ply (El, En tribution, a holding time of 10 min was applied after reaching the required temperature. Heating of the mid- dle section of the specimen is realized by inductive 3. Results and discussion heating of a susceptor. The temperature is measured with the aid of a thermocouple in the middle of the A calculation of the longitudinal and transverse ply specimen. The heating coil with a height of 100 mm and stifness En and Ei with the aid of the moduli of the consisting of 6 windings was adjusted in such a way, two types of crossply specimens delivers the values that the temperature in the 40 mm gauge length was as indicated in Table 4. The modulus parallel to the fibres homogeneous as possible. The maximum temperature can be approximated very well by the rule of mixtures deviation in the gauge length of 40 mm measured + 3% -o% at a temperature of 1200 C in the middle Stress- strain behaviour at all temperatures is measured with the aid of a clip gauge with a gauge length of 20 mm as schematically presented in Fig 4 Fig. 3. Dog-bone specimen dimensions for(0/90/0/90/0/90), tensile Table I Radius of dog-bone specimen(grip length 55 mm) Fig 4. Schematics of experimental set-up for high temperature tensile X0.0001.6122955456758307.78290009931 esting of Nextel 610/Mox Y0.0000.0270.0600.ll80.1790.3140.4320.545 X11.50712.55513.24513.75514.13114.38215000 Y0.8141.0681.2911.4921.6771.8272.50 Test specimens to characterize the mechanical behaviour of Nextel 610/Mox Table 2 Specimen type Test Radius of adapted dog-bone temperature propertie X0.0001612 5.8307.7829.00010 (0/90/0/90/0/90) 10 mm dog-bone RT-1200C E, UTS 0.1790.3140.4320.54 902/02/90 10 mm paral RT X15 (+45/-45/+45/10 mm parallel RT E(G), UTS(S) 1.522012.5 45/+45/-45)Vp=0.159, respectively. The density of the plate reached 3.0015 g/cm3 . Dog-bone type specimens were cut from the plate in 0-direction by waterjet. For a ®rst test ser￾ies waisting of the specimens from a width of 15 mm in the grip range to a 10 mm wide gauge section was per￾formed according to the dimensions in Fig. 3 and Table 1. As most of the specimens tested in the ®rst test series broke near the radius the shape of the specimen was adapted to give a smoother change of width. The x±y coordinates for the changed specimen shape is given in Table 2. The dog-bone specimens were loaded up to failure in a tensile test performed at di€erent temperatures between room temperature and 1200C as a maximum. In order to guarantee a homogeneous temperature dis￾tribution, a holding time of 10 min was applied after reaching the required temperature. Heating of the mid￾dle section of the specimen is realized by inductive heating of a susceptor. The temperature is measured with the aid of a thermocouple in the middle of the specimen. The heating coil with a height of 100 mm and consisting of 6 windings was adjusted in such a way, that the temperature in the 40 mm gauge length was as homogeneous as possible. The maximum temperature deviation in the gauge length of 40 mm measured +3% ÿ0% at a temperature of 1200C in the middle. Stress± strain behaviour at all temperatures is measured with the aid of a clip gauge with a gauge length of 20 mm as schematically presented in Fig. 4. Parallel sided specimens with a width of 10 mm as indicated in Table 3 were also cut from the plates but now with the aid of a diamond wire machine. Specimens cut under an angle of 45 with respect of the 0-direc￾tion are used to measure the shear modulus G and the intralaminar shear strength at room temperature. Fur￾ther 10 mm wide specimens were cut transverse to the 0-direction. After this these specimens were ground with a diamond wheel on both surfaces in order to remove the surface layers so that ®nally specimens with the orientation 900.2/02/900.2 remain. The sti€ness of the crossply specimens with two di€erent relative amounts of transverse plies (V90=50% and V90=16.6% respectively) allows the determination of the moduli of the parallel and transverse ply (E==; E?). 3. Results and discussion A calculation of the longitudinal and transverse ply sti€ness E== and E? with the aid of the moduli of the two types of crossply specimens delivers the values indicated in Table 4. The modulus parallel to the ®bres can be approximated very well by the rule of mixtures: Fig. 3. Dog-bone specimen dimensions for (0/90/0/90/0/90)s tensile test. Table 1 Radius of dog-bone specimen (grip length 55 mm) X 0.000 1.612 2.955 4.567 5.830 7.782 9.000 9.931 Y 0.000 0.027 0.060 0.118 0.179 0.314 0.432 0.545 X 11.507 12.555 13.245 13.755 14.131 14.382 15.000 Y 0.814 1.068 1.291 1.492 1.677 1.827 2.500 Table 2 Radius of adapted dog-bone specimen (grip length 40 mm) X 0.000 1.612 2.955 4.567 5.830 7.782 9.000 10 Y 0.000 0.027 0.060 0.118 0.179 0.314 0.432 0.54 X 15 20 25 30 Y 1.03 1.52 2.01 2.5 Table 3 Test specimens to characterize the mechanical behaviour of Nextel 610/Umox Specimen Specimen type Test temperature Mechanical properties (0/90/0/90/0/90)s 10 mm dog-bone RT-1200C E, UTS 900.2/02/900.2 10 mm parallel RT E (+45/ÿ45/+45/ ÿ45/+45/ÿ45)s 10 mm parallel RT E(G), UTS(S) Fig. 4. Schematics of experimental set-up for high temperature tensile testing of Nextel 610/Umox. P.W.M. Peters et al. / Journal of the European Ceramic Society 20 (2000) 531±535 533