Engineers such as Ding Fulian and Wang Chengzhong from the Technology Center of Baosteel Corporation conducted tests on the method for evaluating the uncertainty of measurement results in tensile tests, and wrote this article "Evaluation Test of Uncertainty in Measurement in Tensile Tests". According to the seven evaluation steps of the degree of certainty to carry out the test, according to different sample shapes, sizes, test personnel, size measuring instruments, testing machine grades, extensometer grades, tensile speeds and other influencing factors, the results in the tensile test are given respectively. Uncertainty evaluation of measurement results of strength indexes RP , ReH , ReL , Rt , Rm , and plasticity indexes A , Z.
Test results: adopt the report form of expanded uncertainty U = ku c (y), and take the inclusion factor k = 2.
R P0.2 =621.3 MPa, U =9.3 MPa, k =2;
R m =733.8 MPa, U =9.4 MPa, k =2;
A=23.08%, U=0.81%, k=2;
Z=71.37%, U=0.84%, k=2.
In addition, the author proposes that the possible factors that affect the uncertainty of the tensile test results include the sampling location of the material, the processing of the sample, the clamping method of the sample, and the axiality of the applied force. However, due to the difficulty of quantification, as long as The tensile test is carried out according to the standard, and the factor in this aspect can be ignored.
