Comparison and Analysis on Tensile Test Results of Several Sampling Methods for Welded Joints

Taking the 304 stainless steel butt-welded test plate as the research object, specimens were taken along the direction of the base metal, full weld and vertical weld, and the rationality of using the transversal tensile test of the welded joints to obtain the yield strength of the weld was discussed. At the same time, the difference in tensile strength and elongation after breaking obtained by using different sampling methods was also studied. The results show that the yield strength obtained from transversal tensile test of the joint was between that of the base metal specimen and that of the full weld specimen. And the yield strengths obtained by using extensometers with different gauge lengths and without extensometer were different. In other words, the yield strength was greatly influenced by the selecting of extensometers. The tensile strength obtained from transversal tensile test of the joint was also between that of the base metal specimen and that of the full weld specimen. However, the elongation after breaking obtained from transversal tensile test of the joint was much lower than those of base metal specimen and full weld specimen.