A DEVICE FOR MEASURING THE TORQUE UPON LOADING THE SUBSTANCE BY THE METHOD OF P. W. BRIDGMAN

A method for measuring the torque upon loading of the substance by the method of P. U. Bridgman is presented. The method provides a strong axial compression of the substance between two punches. At the same time, the compressed substance is additionally exposed to an external action resulted from rotation of one plunger relative to another. The pressure in such experiments can reach 5 GPa or more. The punches are made of hardened steel or hard alloy. The proposed device is a simple and holistic mechanism. It consists of a universal shell, shell, two punches, converter modules, a hollow cylinder and an elastic thin disc. The device is mounted on a unit of complex loading which has a plunger of rotation and axial displacement. The punches are fixed in the shells. The working diameter of the punches and, correspondingly, of the test sample, depending on the experimental conditions, ranges from 5 to15 mm. In special cases the diameter can be more than15 mm. The torque of loaded sample in this device is measured by transducing modules. To increase the sensitivity, the transducing modules are placed beyond the universal shell and are located far from the supporting surfaces of the device. The original design of the transducing module ensures the independence of the force point from the rotation of the punch in the plane perpendicular to the force axis. This feature of the transducing module provides deformation of tensometric resistors under the impact of elastic compression only from the force resulted from the punch rotation. The guaranteed elimination of undesirable interferences allows a qualitative measuring of the torque. The proposed device provides high sensitivity under extreme conditions and desired quality of torque measurements.

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