Tensile strength is the critical value of stainless steel transition from uniform plastic deformation to localized concentrated plastic deformation, but also the maximum bearing capacity under static tension. In short, the essence is the resistance of stainless steel to maximum uniform plastic deformation, symbolized as RM, unit MPa.
1、 Tensile Test of 304 Strip
The 304 strip is made into a specimen, the specimen is pulled off in the tensile testing machine, and then one or several mechanical properties are measured. Usually, only the tensile strength, yield strength, elongation at break, and area shrinkage are measured. The tensile test is the most basic mechanical property test method for metallic materials.
Tensile tests are prescribed for almost all metallic materials, provided they have requirements for mechanical properties. Especially for materials whose shapes are not convenient for hardness tests, tensile tests have become the only means to test their mechanical properties.
2、 Hardness Test
A hard indenter is slowly pressed into the surface of a specimen with a hardness tester under specified conditions, and then the depth or size of the indentation is tested to determine the hardness of the material. The hardness test is the simplest, fastest, and easiest method of testing mechanical properties of materials.
The hardness test is non-destructive and there is an approximate conversion relationship between the hardness value of a material and its tensile strength value. It is of great practical significance to convert the hardness value of the material to the tensile strength value.
China, Japan, and the United States 304 stainless steel standard tensile strength for:
Japanese standard: SUS304, tensile strength greater than 520n/mm2
American Standard: 304, tensile strength greater than 515n/mm2
National standard: 06cr19ni10, tensile strength ≥ 515mpa.
304 strip is the most widely used chromium-nickel stainless steel. As a widely used steel, it has good corrosion resistance, heat resistance, low-temperature strength, and mechanical properties; good hot workability, such as stamping and bending, no heat treatment hardening phenomenon (use temperature -196℃~800℃). It is resistant to atmospheric corrosion. If it is an industrial atmosphere or a heavily polluted area, it needs to be cleaned up in time to avoid corrosion. It is suitable for food processing, storage, and transportation.
In summary, the above is the main content of how to measure the tensile strength of 304 strips. Because the tensile test is not easy to test, and easy to convert from hardness to strength, more and more people only test the hardness of the material and rarely test the strength of the material.
304 stainless steel welded tube
Especially due to the continuous progress and innovation of hardness tester manufacturing technology, some materials that can not be directly tested for hardness, such as 304 stainless steel pipe, 304 stainless steel plate, and 304 Strip, can now be directly tested for hardness. Therefore, the hardness test gradually replaces the tensile test as a trend.