Uncertainty Evaluation on Testing Results of Tensile Strength of Friction Stir Welding Joints of 2A70 Aluminium Alloy

The tensile strength of friction stir welding T-joints of 2A70 aluminium alloy was tested according to GB/T 2651-2008Method of Tensile Test for Welded Joint,and uncertainty of the tensile strength testing results was evaluated.The results show that the expanded uncertainty and relative expanded uncertainty of tensile strength of the T-joints were 14 MPa and 3.8%respectively,when the confidence level was 95%and coverage lactor was 2.Therefore,the uncertainty report can be expressed as follow:R_m=(370±11)MPa.v=81,k=2.