| 摘要 |
PURPOSE:To obtain accurate compliance, by starting unloading after stress relaxation is decreased, by making a load acting on a test piece constant during the period the stress relaxation is waited in a stable breakdown region, thereby eliminating the stress relaxation. CONSTITUTION:An actuator 5 is operated and a load is made to act on a CT test piece 1. A load/displacement curve is recorded by a load cell 3 and a displacement gage 2. When the opening displacement reaches a specified value, the load increase is stopped, and the relaxation of internal stress is waited. The stress relaxation is detected by the cell 3. When the decreasing speed no longer give effect to the measuring error of the compliance, the actuator 5 is operated by a controller 6 and the load is removed by one action. Thus the compliance is obtained. In comparison with the unloading in association with the stress relaxation, the test time can be shortened. The effect of the stress relaxation on the measured data can be prevented. The compliance in the stabilized breakdown region can be accurately obtained. |
