Difference Analysis on Sampling Standards and Mechanical Property Tests Standards of Domestic and Abroad Hot-rolled Structural Steels

Three kinds of commonly used hot-rolled steel (Q345B steel, S355JR steel and Gr.50 steel) structure plates and shapes were chosen to analyze the content difference of Chinese standard, European Union standard and United States standard from the aspects of sampling position, sampling direction, mechanical properties testing and so on. The analysis results show that: in terms of sampling, Chinese standard was the same with European Union standard on the whole, but different from United States standard; in terms of mechanical property test, when the sampling locations were the same, the strength increased but the plasticity decreased with the increase of the testing speed; the impact absorbing energy of United States standard was generally larger than that of Chinese standard and European Union standard. In order to obtain the exact results, not only the commonly used test standards should be mastered, but also domestic and overseas standard systems should be known well. The standard of general delivery technical conditions etc. should be mastered as well as the products standard to ensure the quality of the testing work.