测定固体线膨胀系数的一种方法

A method for determining the solids coefficient of linear expansion

当两个光栅紧靠在一起时，从它们的透射光中将看到明暗相间的条纹。该条纹间距与两个光栅夹角有关，若我们把一个光栅固定在随金属丝的伸长而绕某一定轴转动的支架上，则根据该转轴到金属丝间距和条纹间距及其它的变化量，就很容易得出金属丝随温度升高而伸长的微小量与条纹间距变化量之间的关系，并通过它算出该金属丝的线膨胀系数。

When two optical gratings were closed tightly each other, the transmission light format striation which have relation to the intersection angle of the two optical gratings. One of the two optical gratings was fixed on a stand that can be rotate on a fixd axis,and the variation of metal wire's length could lead to its rotating. The relation between the variations of metal wire's length and the strip spacing could be determined by both the distance between the axis and metal wire and the variation of stripe spacing, and it could determine the metal wire's coefficient of linear expansion.