BARRIER AND RESOLVENT OF AUTOMATIC MEASUREMENT FOR PERCENTAGE ELONGATION AFTER FRACTURE BY TENSILE MACHINES

There are a lot of tensile machines that carry on tensile test automatically or semi-automatically. Generally these machines can get good accuracy for tensile strength and yield strength values but not for the percentage elongation after fracture when specimen is not broken at middle part of extensometer. The direct measure results and corrected results by different methods are reported. The opinion to replace the percentage elongation after fracture with percentage of total extension at maximum force is put forward.