Abstract:
Through the comparative analysis of ASTM E 837-08, ASTM E 837-13 and ASTM E 837-20 edition standards, it is found that ASTM E 837-20 has the most complete description of residual stress measurement method, which is added the measurement method of medium thickness workpiece that is lacking in the 08 and 13 versions. Besides, the version 20 adopts several commonly used regularization design schemes of hole diameter, hole depth and workpiece thickness, and introduces aperture coefficient, stress depth coefficient and workpiece thickness coefficient. The new calculation formulas of aperture coefficient, stress depth coefficient and workpiece thickness coefficient are added to simplify the calculation of the stress release calibration constant under the conditions of actual aperture, stress depth and workpiece thickness, and eliminate a lot of tedious table lookup work, which facilitates the understanding and operation of standard users. In addition, the specification of the version 20 on workpiece thickness, lower limit of drilling speed, drilling eccentricity distance and the scope of application of meas urement results has differences compared with those of the versions 08 and 13, and the version 20 lowers the requirements and expands the scope of use of the standard. In general, ASTM E 837-20 has improved its applicability and operability, and makes the logic more clear.