Impact of Clamping Positions of Rectangular Tensile Specimens on Strength of Metal Materials

Effect of clamping positions of rectangular tensile specimens on the measurement values of strength was studied through room temperature tensile test to X70 and S690QL steel plate. The results show that under the same condition of tester, machine, material, method and circumstance, when the specimens were clamped on the edge of the chuck or in the middle of the chuck, the measured lower yield strength ReL, higher yield strength ReH and tensile strength Rm are almost the same, but clamping specimens on the edge of the chuck would result in abnormal of elastic deformation stage of the stress-strain curve and affect measurement values of the proof strength plastic extension Rp0.2 and the proof strength total extension Rt0.5.