Tensile test and study on the mechanical properties of stainless steel tubes

Pipe plastic processing is easy to meet the requirements of plastic forming products in terms of lightweight, toughness, low consumption, high efficiency, and precise manufacturing. It has become an important direction of research and development of advanced plastic processing technology in the 21st century. Pipe parts have been widely used in aerospace, automotive, petrochemical, light industry and transportation industries.” In recent years, with the development of thin-walled pipe processing technology, thin-walled stainless steel pipes have higher strength than thin-walled aluminum alloys. The price of tube is lower than that of thin-walled titanium alloy tube, so it has developed rapidly.

In-depth research on the characteristics of plastic forming and deformation laws of pipes needs to be based on accurately obtaining the mechanical properties of the material. However, the current research on material properties is mostly focused on plates, and there are few studies on the mechanical properties of pipes. Due to the different production processes, the basic mechanical properties of pipes and plates are different. The study found that when the profile material is the same, the thickness and the cross-sectional shape are different, the basic mechanical properties are also quite different; different heat treatment conditions, the performance difference is greater. 3. Therefore, to obtain accurate mechanical performance data of the material, it is necessary to In-depth experimental research on pipes. This article aims at 7 different specifications of 2169 stainless steel pipes and 3 different specifications of 321 stainless steel pipes, using arc specimens or pipe section specimens, and the basic mechanical properties of the materials are obtained based on the uniaxial tensile test. It provides a reference for the above-mentioned stainless steel tube prospective forming analysis.

1) Obtain the elastic modulus, yield strength, tensile strength, elongation, strength coefficient, hardening index and plastic strain ratio of 7 specifications of 21-69 stainless steel pipes.

21-69 stainless steel pipe has high strength and poor plasticity, and its mechanical properties are not conducive to deep drawing and bending plastic forming.

2) Obtain the elastic modulus, yield strength, tensile strength, elongation, strength coefficient, hardening index and plastic strain ratio of 3 specifications of 321 stainless steel pipe. Compared with 21-69 stainless steel pipe, 321 stainless steel The tube has low strength and good plasticity.

3) The mechanical performance parameters of 21-69 stainless steel pipe with a thickness of Φl25mmxa02mm were obtained through the tensile test of the arc specimen and the pipe section specimen. It was found that the elongation obtained by the pipe section specimen was greater than the elongation obtained by the arc specimen. The strength and tensile strength are slightly less than the yield strength and tensile strength obtained by the curved specimen