レーザ干渉法を利用し角縦弾性係数の測定

抄録

An apparatus for the measurement of Young's modulus and its thermal coefficient has been newly developed. Both the tension and bending methods are available in this apparatus. The elongation in the tensile test or the deflection in the three-point bending test is detected by using a specially designed sample holder together with a He-Ne laser interferometer with an accuracy of better than 0.1 μm. This apparatus is especially suitable for such thin specimens as leaf springs and hair springs which are often used in precision machines or measuring instruments. The minimum size of specimen to be measured is 0.1 mm in diameter or 5 μm in thickness. Young's modulus of ordinal materials can be measured with an accuracy of better than ±3% in 95% confidence interval. Young's moduli measured by the tension method and bending method were compared with each other and the result showed a good agreement. Thermal coefficients of Young's modulus of six kinds of spring materials were also measured by means of the bending method in the temperature range between 0°C and 50°C.