Influence of Testing Machine Flexibility on Tensile Test Results

Tensile properties of 12 groups of automotive steel plates with relatively stable mechanical properties and produced by different processes were tested on two tensile testing machines with different flexibility in crosshead separation rate controlling mode. The results show that the values of ReH and Rp0.2 which were tested on machine with wedge fixtures and higher flexibility were less than those tested on machine with hydraulic pressure horizon-push fixture and lower flexibility, while the testing machine flexibility had little influence on the values of ReL, Rm and elongation A. The results not only proved the importance and necessity of method A in the new national standard GB/T 228.1-2010, but also gave the proposal about the implementation of method A according to different test conditions.