Brief introduction: Test system adopted at present the most low temperature drift of double-frequency laser heterodyne interferometer, solved the past must have strict performance test under the condition of vibration isolation for ultra low thermal expansion problem, and test temperature range covers - 20 ℃ to 1600 ℃ temperature range, can completely satisfy the at present, most of the low expansion material thermal expansion performance and high precision measurement. Laser interferometry thermal expansion test system adopted by the two-frequency laser heterodyne interferometry is the length of the laser wavelength as a benchmark measuring equipment, laser interferometry thermal expansion performance measurement has become an absolute measurement method, the eliminating vibration, temperature drift, gas refractive index, temperature gradient and slope deformation after a series of influence factors, this test system can be applied to all other thermal expansion performance test methods and test equipment calibration. Features: 1. Adopt double-frequency laser heterodyne interferometry, provides a higher signal-to-noise ratio than other laser interferometry. 2. The temperature accuracy of plus or minus 0.05 ℃ constant temperature water bath. Make the laser interferometer in a state of constant temperature, effectively guarantee the measurement precision of dilatometer. 3. Equipped with the corresponding vacuum control device, make the vacuum degree of vacuum box keeps about 100 pa, the refraction index of gas that can both eliminate the influence, and can keep the vacuum box the heat transfer efficiency of the gas will not reduce. 4. Configuration adjusting mechanism, can help the operator to complete the interferometer precise registration. 5. Is used under 200 ℃ circulating oil bath temperature control mode, in more than 200 ℃, adopted the graphite heater electric heating mode. 6. The sample vertical structure, can measure the thermal expansion of all kinds of rigid and elastic body materials along with the change of temperature, minimum specimen thickness can reach 1 mm. Technical indicators: 1. Range: 2 mm 2. Resolution: + / - 0.5 nm 3. The displacement measurement accuracy: + / - 5 nm 4. The displacement measurement repeatability: plus or minus 3 nm 5. Measuring temperature range: - 40 ℃ ~ 200 ℃, low temperature floor basis of oil bath temperature range), 200 ℃ ~ 1400 ℃ (graphite heater electrical heating) 6. Sample shape: plate, rod, block 7. Sample size: cross-sectional area size; The thickness of 5 mm to 100 mm. 8. The test atmosphere: 100 pa gas (air or inert gas) under pressure 9. Test method: ASTM E289.
Brief introduction: Test system adopted at present the most low temperature drift of double-frequency laser heterodyne interferometer, solved the past must have strict performance test under the condition of vibration isolation for ultra low thermal expansion problem, and test temperature range covers - 20 ℃ to 1600 ℃ temperature range, can completely satisfy the at present, most of the low expansion material thermal expansion performance and high precision measurement.
