CONTROL METHOD IN MATERIAL TESTING DEVICE AND MATERIAL TESTING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a subject control method capable of holding the vertical stress applied to the shearing surface of a material test piece vertically to an almost constant state and a material testing device. SOLUTION: In a control method in a material testing device, a material test piece 1 is housed in a chamber 2, and the pressure in the chamber is made higher than atmospheric pressure and compression load is applied to the material test piece by a compression actuator 9. The compression load F applied to the material test piece 1 is increased by the compression actuator 9 and the pressure in the chamber 2 is lowered as an increase in this compression load and the vertical stressσn applied to the shearing surface (b) of the material piece 1 vertically is made kept almost constant.