BS ISO 17095:2013 pdf free
BS ISO 17095:2013 pdf free.Fine ceramics (advanced ceramics, advanced technical ceramics)
The fixture material shall be as inert as possible for the test conditions used. The fixture shall be oxidation resistant if the testing is conducted in air. The fixture shall have negligible chemical reaction with and shall not contaminate at the test piece. The fixture shall remain elastic over the load and temperature ranges used. The bearing may be made of a ceramic with an elastic modulus of between 200 GPa and 500 GPa and a flexural strength greater than 250 MPa at elevated temperature. Silicon carbides are suitable as the fixture materials. Hot-pressed or sintered silicon carbides with low additive content are elastic up to temperature in excess of 1 500°C. Siliconized silicon carbides and high purity alumina are less expensive, but can exhibit creep deformation at temperatures over 1 200 °C.
A rectangular test bar with a square section shall be prepared before bonding, as shown in Figure 4. The vertical angle tolerance of adjacent faces should be within 19. Table 2 shows the recommended dimensions of the bars with the section size of 4 × 4 mm2, and the length should be larger than 12 mm. The parallelism tolerance on opposite longitudinal face is 0,015 mm. All of the bar samples shall not be chamfered.
To measure the tensile bond strength, place each test piece in the fixture using an arc-shaped pressure head or ball-shaped pressure head, as shown in Figure 5. The cross-bonded sample should be inserted in the test fixture without any friction. The width of the pressure head shall be the same as that of the bar,and the pressure head should be parallel to the lower bar. The test pieces shall be heated to the set test temperature. Care shall be taken to ensure that the thermal expansion of the furnace does not cause the test piece preload to exceed 5 % of the expected average breaking force; it is preferable that the preload be zero. When the test temperature is reached, the test piece shall be held at this temperature, allowing sufficient time for the specimen to reach temperature equilibrium. The time allowed for this shall be stated in the test report. The temperature measured by the thermocouple or other measuring device shall not vary during the time of testing by more than±2 °C. Apply the test force at the specified rate and record the peak load at fracture. Measure the peak load with an accuracy of±1 % or better.BS ISO 17095 pdf download.
