On the Stress Measurement Method Using Slip Lines in Copper Foil with Grown Grain Structure : Solid-Mechanics, Strength of Materials

By observing slip lines in a copper foil with grown grain structure, the method of measuring cyclic stresses acting on machine elements is studied. The features and distinction of this method in comparison with the copper electroplating method or the method using a recrystallized foil are examined. This method is superior to the method using a recrystallized foil from the standpoint of ease of measurement, and its strain sensitivity is much higher than that of the electroplating method. As an application of this method, the stress concentration factors in various types of circular shafts with a flat part under cyclic torsion are obtained, with the results showing good agreement with those obtained previously.